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Teacher’s EditionSampler
CourSE 1
Teacher’s EditionSampler
Grade 6
CourSE
1
B
Title
advanced proofs not final pages
This Math in Focus Course 1 sampler provides one full chapter from the Grade 6 program that will be available for Fall 2011.
Courses 2 and 3 for Grades 7 and 8 will be coming soon!
ArrivingFall 2011
Course 2
A
Arriving2012
Arriving2012
CourSE 1 Teacher’s Edition Sampler
* PaGes in This samPler are advanced ProoFs and noT Final PaGes
Grades 1–5
1
Table of Contents
The Story Behind Math in Focus™ ...................2
Singapore Math Framework ...........................6
Instructional Pathway .....................................8
Extensive Teacher Support ........................... 12
Transition Support ........................................ 16
CourSE 1 Table of Contents .......................... 18
CourSE 1 Chapter 7 Algebraic Expressions ...................................................27
Scope and Sequence: Grades 4–6 ...............65
Program Components ..................................78
CourSE 1 Teacher’s Edition Sampler
2 advanced proofs not final pages
Background: History of the Development of Singapore Math TextbooksFrom 1965 to 1979, many of the primary and secondary textbooks (and all mathematics textbooks) used in singapore had been imported from other nations. But starting in 1980, singapore began to take a new approach. The curriculum development institute of singapore (cdis) was set up to develop primary and secondary textbooks for the new education system. This initiative produced new developments in learning that propelled singapore’s math students to the top of the international community. most schools in singapore today use programs published by marshall cavendish education.
1. Gonzales, Patrick, Juan carlos Guzmán, lisette Partelow, erin Pahlke, leslie Jocelyn, david Kastberg, and Trevor Williams. Highlights From the Trends in International Mathematics and Science Study: Timss 2003. U.s. department of education, national center for education statistics, 2004.
2. national council of Teachers of mathematics. Curriculum Focal Points for Prekindergarten through Grade 8 Mathematics, 2006.
3. national mathematics advisory Panel. Foundations for Success. U.s. department of education, 2008.
4. american institutes for research® What the United States Can Learn from Singapore’s World-Class Mathematics System. U.s. department of education Policy and Program studies services, 2005.
5. national research council. adding It Up: Helping Children Learn Mathematics. Washington, dc, national academy Press, 2001.
6. ministry of education, singapore. Mathematics Syllabus: Primary, 2007.
Footnotes
Math in Focus: Singapore Math Course 1 is a mathematics program created specifically to address the recommendations for instructional materials agreed upon by national and international panels of mathematics education specialists. Aligned to the Common Core State Standards, Math in Focus provides world-class mathematics instruction that meets the specific needs of U.S. students.
Meeting the Needs of u.S. Classrooms...Top performing countries have gained ground on, and now surpass the U.s. in mathematics education, as shown by the Trends in international math and science study (Timss)1. efforts to reverse this trend have led to a large body of solid research. analysis of the research base has led the national council of Teachers of mathematics (ncTm)2, the national math advisory Panel3, the american institutes for research®4, and the national research council5 to make several undisputed key recommendations:
1 a focused, coherent curriculum, without significant repetition year after year
2 an equal emphasis on conceptual understanding and fluency with skills
3 Use of concrete and pictorial representations
4 multi-step and non-routine problem solving
...by Drawing on Success in SingaporeThe research base used to guide the common core state standards noted that singapore students have been top performers on the Timss assessment since 1995. Their success can be largely attributed to the mathematics curriculum revision implemented by the singapore ministry of education6 in the 1980s.
Key requirements of their instructional materials that parallel the recommendations of u.s. specialists are:
• Precise framework of concepts and skills (specifics of what to exclude, as well as what to include, provides hierarchy and linkage)
• Skills and concepts taught in depth to allow for mastery (consolidation of concepts and skills)
• use of a concrete-to-visual-to-symbolic development of concepts using model drawings to connect visual representation to problem solving
• Emphasis on problem solving considered central to all mathematics study
Grades 1–5
3advanced proofs not final pages
Foreshadow Specific Future Concepts
Draw on Solid Prior Knowledge
Skill Building
Concept Building
the WHY
Math in Focus is the SolutionMath in Focus: Singapore Math by Marshall Cavendish embodies the world-class Singaporean pedagogy, methodology, and instructional materials while adapting the Singaporean mathematics standards to correspond to the Common Core State Standards for Mathematics outlined by the National Governors Association for Best Practices and the Council of Chief State School Officers in the United States. The Common Core State Standards conclusions parallel the assumptions behind Math in Focus.
market research for Math in Focus included multiple rounds of research including focus group testing and discussions with experienced educators. regional and national studies ensured that the student books and teacher support meet the current needs of students and teachers across the U.s.
For more details, visit greatsource.com/mathinfocus
• Teach to Mastery Math in Focus helps students build solid conceptual understanding through the use of visual models. Math in Focus authors created a strategic, articulated sequence of topics developed in depth to mastery. rather than repeating topics, students master them in a grade level and subsequent grades develop them to more advanced levels. students learn the “how” and the “why” through instruction, hands-on activities, and practice.
• Focused and Coherent CurriculumMath in Focus is organized to teach fewer concepts at each level, but to teach them thoroughly. When a concept appears in a subsequent grade level, it is always at a higher level.
• Clear Visuals and Use of ModelsMath in Focus consistently employs a concrete-visual-symbolic progression. clear and engaging visuals that present concepts and model solutions allow all students to focus and better understand abstract concepts.
• Organize Topics by Big Ideasin course 1, the common core state standards have identified four big ideas in ratio and proportion, number, algebra, and statistics. Math in Focus is divided into two books, roughly a semester each. about 75% of Book a is devoted to the big ideas in ratio and proportion, number, and algebra. These key topics are in the beginning of the school year so students have a whole year to master and review them. common core state standards correlations are provided for every chapter.
how can i simplify this equation?
4 advanced proofs not final pages
The Story Behind Math in Focus
Singapore Math Foundations are Supported by research
singapore ministry of education
“mathematical problem solving is central tomathematics learning. it involves the acquisition and application of mathematics concepts and skills in a wide range of situations, including non-routine,open-ended, and real-world problems.”
—Mathematics Syllabus: Primary, 2006
Math in Focusaddresses fewer topics in greater depth
at each level.
• Knowledgeisbuiltcarefullyandthoroughlywithboth multi-page lessons and multi-day lessons.
• Timeisbuiltintotheprogramtodevelopunderstanding with activities, as well as ample scaffolded, guided practice with every learn and extensive skills practice.
Math in Focusdevelops concepts to mastery
at each level.• Studentsaregivenscaffoldedsupportwith
instruction, activities, and ample guided practice.
• Skillsareconnectedtoconceptsthroughvisualrepresentations for understanding the “how” and the “why.”
• Extensiveproblemsolvingmergesconceptualunderstanding with computational skills for mastery.
national council of Teachers of mathematics
“a curriculum is more than a collection of activities: it
must be coherent, focused on important mathematics,
and well articulated across the grades.”
—Curriculum Focal Points for Prekindergarten through Grade 8 Mathematics, 2006
Focused and Coherent Curriculum Teach to Mastery
Skill Building
Concept Building
the WHY
the HoW
7.1 Writing Algebraic expressions
7.2 evaluating Algebraic expressions
7.3 simplifying Algebraic expressions
7.4 expanding and Factoring Algebraic expressions
7.5 real-World Problems Algebraic expressions
Chapter 7- Algebraic expressions
5advanced proofs not final pages
The Story Behind Math in Focus
national research council
“opportunities should involve connecting symbolic representations and operations with physical or pictorial representations, as well as translating between various symbolic representations.”
—Adding it Up: Helping Children Learn Mathematics, 2001
Bar Model: a visual representation of a word problem (Grade 2)
Math in Focususes visual models for presenting concepts,
focusing on a meaningful transition to the symbolic.
• Thevisualrepresentationofwordproblemswithbar models leads to symbolic solutions of rich and complex problems.
• Minimaltextanddirectvisualsallowstudentstofocus on key concepts.
• Consistentuseofconcrete-visual-symbolicpedagogy leads to conceptual understanding.
Clear Visuals and Use of Models
common core state standards for mathematics
in Grade 6, instructional time should focus on four critical areas: (1) connecting ratio and rate to whole number multiplication and division and using concepts of ratio and rate to solve problems; (2) completing understanding of division of fractions and extending the notion of number to the system of rational numbers, which includes negative numbers; (3) writing, interpreting, and using expressions and equations; and (4) developing understanding of statistical thinking.
—Common Core State Standards for Mathematics: corestandards.org
Math in Focusfollows an articulated scope and sequence
focused on key middle school math concepts.• Lessoncontentbuildsstrongnumberconcepts
and algebraic thinking.
• Contentisfocusedonbuildingfoundationsfornumbers, operations, ratios, proportions, algebraic expressions, and equations.
Organize Topics by Big Ideas
6 Chapter 7 Algebraic Expressions
Le
arn
4z is the only term of the
expression 4z.
You can say that 4z is the
product of z and 4.
Use variables to write multiplication expressions.
a) There are 12 crackers in each box. How many crackers are there in 2 boxes?
?
12
2 3 12 5 24
There are 24 crackers in 2 boxes.
b) There are z crackers in each box. How many crackers are there in 4 boxes?
?
z
4 3 z 5 4z There are 4z crackers in 4 boxes.
4z is an algebraic expression in terms of z.
Guided PracticeWrite an algebraic expression for each of the following.
1 The sum of x and 10.
2 The difference of y and 7.
3 Jim is now z years old.
a) His brother is 4 years older than Jim. Find his brother’s age in terms of z.
b) His sister is 3 years younger than Jim. Find his sister’s age in terms of z.
© 2010. National Governors Association Center for Best Practices and Council of Chief State School Officers. All rights reserved.
36 Chapter 7 Algebraic Expressions
Chapter Wrap UpConcept Map
are combined
and simplified
to form
can be
translated to
can be
Algebraic Expressions
Numbers
(coefficients)
Real-lifesituations
(in word problems)
Operational signs
1, 2, 3, 4
Variables
Evaluated FactoredExpanded
Key Concepts
A letter or variable in an algebraic expression represents an unknown specific
number or any number.
The expression x 1 x 1 x 1 x… (20 terms) is equivalent to 20x.
Expanding and factoring are inverse operations.
6 advanced proofs not final pages
Singapore Math Framework
Math in Focus student Books help students build problem solving ability through an instructional pathway of:
• learning concepts and skills through visual lessons and teacher instruction
• consolidating concepts and skills through practice, discussion, and activities
• applying concepts and skills with extensive problem solving practice and challenges
Singapore’s Approachto Becoming Strategic Mathematical Problem SolversMath in Focus is built around the Singapore Ministry of Education’s pentagon that emphasizes conceptual understanding, skill development, strategies for solving problems, attitudes towards math, and metacognition.
Singapore‘s Mathematics Framework
From the Singapore Ministry of Education
The center of the pentagon is problem solving. The primary goal of Math in Focus is to enable students to become strategic mathematical problem solvers.
Grades 1–5
7advanced proofs not final pages
Building a Solid Foundation for Problem Solving
diagrams are used to present examples with solutions.
Visual
only numerals, mathematical notation, and symbols are used once students are familiar with the abstract representation.
7Lesson 7.1 Writing Algebraic Expressions
Le
arn
?
12 in.
Use variables to write division expressions.
a) A 12-inch rod is divided into 3 parts of equal length.
What is the length of each part?
12 4 3 5 4
The length of each part is 4 inches.
b) A rod of length w inches is divided into 7 parts of equal length. What is the
length of each part?
?
w in.
The length of each part is (w 4 7) inches or w7
inches.
w7
is an algebraic expression in terms of w.
Guided PracticeWrite an algebraic expression for each of the following.
4 The product of z and 6.
5 The quotient of w and 8.
6 Mia bought a pair of shoes for p dollars. She also bought a dress that cost 5 times as
much as the shoes, and a belt that cost 14
of the price of the shoes.
a) Find the cost of the dress in terms of p.
b) Find the cost of the belt in terms of p.
Math Note
w7
can also be written as 17
w.
w7
is the only term of the expression w7
.
You can say that w7
is the quotient of w and 7.
w is the dividend and 7 is the divisor.
18 Chapter 7 Algebraic Expressions
Le
arn
Le
arn
Use order of operations to simplify algebraic expressions.
a) Simplify x 1 6x 1 2x.
x 1 6x 1 2x 5 7x 1 2x Work from left to right.
5 9x Add.
b) Simplify 7x 2 5x 2 x.
7x 2 5x 2 x 5 2x 2 x Work from left to right.
5 x Subtract.
c) Simplify 9x 2 3x 1 2x.
9x 2 3x 1 2x 5 6x 1 2x Work from left to right.
5 8x Add.
Guided PracticeSimplify each expression.
21 j 1 3j 1 2j 5 ? 1 2j 22 4j 1 5j 1 2j
5 ?
23 9t 2 3t 2 4t 24 5t 2 t 2 4t
25 8w 2 6w 1 3w 26 7w 1 2w 2 6w
CautionWhen adding and subtracting
algebraic terms with no parentheses,
always work from left to right.
For example:
7x 2 5x 2 x 7x 2 4x9x 2 3x 1 2x 9x 2 5x
Collect like terms to simplify algebraic expressions.
a) The figure shows a parallelogram. Find the perimeter of the parallelogram.
8 cm
8 cm
r cm r cm
r 1 8 1 r 1 8 Identify like terms.
5 r 1 r 1 8 1 8 Change the order of terms
to collect like terms.
5 2r 1 16 Simplify.
The perimeter of the parallelogram is
(2r 1 16) centimeters.
Math Note
Commutative Property of Addition:
Two numbers can be added in
any order.
So, 4 1 a 5 a 1 4.
4 Chapter 7 Algebraic Expressions
Le
arn
7.1 Writing Algebraic Expressions
Vocabularyvariable
algebraic expression
terms
Lesson Objective• Usevariablestowritealgebraicexpressions.
A variable can be
replaced by different
values. x is a variable,
so it can represent
different values.
If the length of the first
ribbon is 12 in., then
x is 12.
You can use a letter, called
a variable, to represent
the unknown length.
Use variables to represent unknown numbers and write addition expressions.
a) A 5-inch ribbon is taped to an 8-inch ribbon. What is the total length of the
two ribbons?
?
8 in.5 in.
5 1 8 5 13
The total length of the two ribbons is 13 inches.
b) A ribbon of unknown length is taped to a 9-inch ribbon. What is the total length
of the two ribbons?
Let the length of the first ribbon be x inches.
?
9 in.x in.
Math Notes contain helpful reminders to students.
Cautions contain common mistakes and misconceptions.
Models are used to help students visualize mathematical concepts.
side notes are used to reinforce student understanding.
Symbolic
2x + x = 3x
each lesson in the student Book is introduced with a Learn element. mathematical concepts are presented in a straightforward visual format, with specific and structured learning tasks and worked-out examples.
8 advanced proofs not final pages
consolidates learning.
8 Chapter 7 Algebraic Expressions
Write an algebraic expression for each of the following.
1 The sum of 4 and p. 2 The difference of q and 8.
3 The product of 3 and r. 4 The quotient of s and 5.
5 Cheryl is now x years old.
a) Her father is 24 years older than Cheryl. Find her father’s age in terms of x.
b) Her brother is 2 years younger than Cheryl. Find her brother’s age in terms of x.
c) Her sister is twice as old as Cheryl. Find her sister’s age in terms of x.
d) Her cousin is 13
Cheryl’s age. Find her cousin’s age in terms of x.
6 Multiply k by 5, and then add 3 to the product.
7 Divide m by 7, and then subtract 4 from the quotient.
8 Divide j by 9, and then multiply the quotient by 2.
9 The sum of 13
of z and 15
of z.
Solve.
10 Jeremy bought 5 pencils for w dollars. Each pen costs 35¢ more than a pencil.
Write an algebraic expression for each of the following in terms of w.
a) The cost, in dollars, of a pen.
b) The number of pencils that Jeremy can buy with $20.
11 The figure shown is formed by a rectangle and a square. Express the area of the
figure in terms of x.
x cm
7 cm
3 cm
Practice 7.1
30 Chapter 7 Algebraic Expressions
Le
arn Write a multiplication or division algebraic expression for a real-world problem and evaluate it.
A car uses 1 gallon of gas for every 25 miles traveled.
a) How far can the car travel on w gallons of gas?
1 gallon
w gallons
25 miles 25 miles 25 miles25 miles
1 gallon 25 miles
w gallons w 3 25 5 25w miles
The car can travel 25w miles on w gallons of gas.
Guided PracticeComplete.
1 Raoulisyyearsold.Kaylais6yearsolderthanRaoulandIsaacis4yearsyounger thanRaoul.
a) Find Kayla’s age.
Kayla is ? years old.
y 6
?
b) Find Isaac’s age.
Isaac is ? years old.
y
4?
c) If y 512,findthesumofRaoul’sageandIsaac’sage.
When y 5 12,
Isaac’s age:
? 2 ? 5 ? 2 ?
5 ?
SumofRaoul’sageandIsaac’sage:
? 1 ? 5 ?
ThesumofRaoul’sageandIsaac’sageis ? .
14 Chapter 7 Algebraic Expressions
Solve.
5 A square has sides of length x centimeters. Find the perimeter of the square
in terms of x.
x cm
?
? ? ?
x 1 ? 1 ? 1 ? 5 ?
The perimeter of the square is ? centimeters.
6 The figure shows a trapezoid. The length of each side is given as shown. Find the
perimeter of the trapezoid in terms of w.
w cm
?
? ? ?
w 1 ? 1 ? 1 ? 5 ?
The perimeter of the trapezoid is ? centimeters.
Guided PracticeSimplify each expression. Then state the coefficient of the variable in the expression.
1 x 1 x 1 x 1 x 1 x 2 y 1 y 1 6
3 m 1 m 1 m 1 5 1 4 4 n 1 n 1 n 1 n 1 n 1 n 1 12 2 8
x cm
10 cm
w cm w cm
w cm
Consolidating Concepts and Skillsfor Deep Math Understanding
Extensive Practiceeach Learn portion of the lesson is followed by opportunities to develop deeper understanding through these features:
• carefullycraftedskillspracticeinthelesson using Guided Practice and Practice
• real-worldproblems
• additionalpracticeproblemsintheExtra Practice Book and advanced practice in the enrichment Book
Guided Practice allows students to check their understanding while working with some guidance.
34 Chapter 7 Algebraic Expressions
Practice 7.5
1 Jenny is x years old. Thomas is 3 times as old as she is. Jenny is 5 years older
than Alexis.
a) Find Alexis’s age in terms of x.
b) Find Thomas’s age in terms of x.
c) If x 5 12, how much older is Thomas than Jenny?
2 A van travels from Town A to Town B. It uses 1 gallon of gas for every 24 miles
traveled.
a) How many gallons of gas does the van use if it travels 3x miles?
b) The van uses 2y gallons of gas for its journey from Town A to Town B.
Find the distance between Town A and Town B.
3 Brian bought x apples and some oranges. Brian bought 3 more oranges
than apples.
a) Find the total number of fruits Brian bought in terms of x.
b) Find the total amount of money, in cents, that Brian spent on the fruits.
Give your answer in terms of x.
c) If Brian could have bought exactly 12 pears with the amount of money
that was spent on the apples and oranges, find the cost of each pear,
in cents, in terms of x.
4 A rectangle has a width of x centimeters and a perimeter of 8x centimeters.
A square has sides of length 14
that of the length of the rectangle.
a) Find the length of the rectangle.
b) Find the perimeter of the square.
c) Find the difference between the perimeter of the square and the
perimeter of the rectangle if x 5 4.
d) Find the difference between the area of the rectangle and the area of
the square if x 5 4.
Instructional Pathway
Practice
9advanced proofs not final pages
Hands-on Work in Pairs and Small Groupsstudents develop concepts and explore connections as they practice skills and communicate their reasoning processes.
Hands-on and Technology Activities reinforce skills, concepts, and problem solving strategies in small-group or partner settings.
Chapter Wrap up serves as a recap of the key concepts in the chapter. The concept map is a graphic organizer that shows the relationships between key concepts.
24 Chapter 7 Algebraic Expressions
STEP
1 Draw a rectangle that is greater than 3 centimeters long and 8 centimeters
wide on a piece of paper. Then cut out the rectangle.
(p 1 3) cm
8 cm
STEP
2 Find the area of the rectangle in terms of p.
STEP
3 Then cut the rectangle into two rectangles A and B as shown.
(p 1 3) cm p cm
A B8 cm 8 cm
3 cm
8 cm
STEP
4 Find the areas of rectangle A and rectangle B.
STEP
5 UsingyouranswersfoundinSTEP
2 and STEP
4 , state how the three areas are related.
STEP
6 You may repeat the activity using rectangles of other sizes.
RECOGNIZE THAT EXPANDED EXPRESSIONS ARE EQUIVALENT
Materials:
• paper
• ruler
• scissors
15Lesson 7.3 Simplifying Algebraic Expressions
Work in pairs.
STEP
1 Make the following set of paper strips.
Let the length of the shortest strip be m units. Make and label 5 such strips.
RECOGNIZE THAT SIMPLIFIED EXPRESSIONS ARE EQUIVALENT
Materials:
• paper
• ruler
• scissors
m mm m m
Make and label 4 more strips of lengths 2m units, 3m units, 4m units, and 5m units.
2m 3m
4m 5m
STEP
2 Take one of the longer strips and place it horizontally.
Example
3m
STEP
3 Ask your partner to use the pieces of the shortest strips to match the length of the
chosen strip in STEP
2 .
Example
STEP
4 Write an algebraic expression to describe the number of short strips used, and
simplify it. For example in STEP
3 , write m 1 m 1 m 5 3m.
STEP
5 Repeattheactivitywithotherlengthsofstrips.
How do the lengths of the strips show that the expressions
are equivalent?
Chapter review/Test can be used as either review exercises or formal assessment. additional chapter Tests are also provided in the assessments component.
37Chapter 7 Algebraic Expressions
Chapter Review/TestConcepts and SkillsWrite an algebraic expression for each of the following.
1 A number that is 5 more than twice x.
2 The total cost, in dollars, of 4 pencils and 5 pens if each pencil costs w cents
and each pen costs 2w cents.
3 The length of a side of a square whose perimeter is r units.
4 The perimeter of a rectangle whose sides are of lengths (3z 1 2) units and
(2z 1 3) units.
Evaluate each expression for the given value of the variable.
5 3(x 1 4) 2 x2
when x 5 2 6 5 9
2p 1
1 2 5
3p 1
when p 5 5
Simplify each expression.
7 24k 1 11 2 5k 2 4 8 10 1 13h 2 6 2 4h 1 9 1 12h
Expand each expression.
9 5(m 1 3) 1 2(m 1 8) 10 9(x 1 2) 1 4(5 1 x)
Factor each expression.
11 5a 2 25 12 28 2 7x 13 12z 1 28 2 7z 2 3
State whether each pair of expressions are equivalent.
14 3(x 1 5) and 5(x 1 3) 15 6y 2 26 and 2(3y 2 13)
16 18 2 12p and 3(5 1 6p) 1 3(2p 1 1) 17 15 2 5q and 5(q 2 3 )
Problem SolvingSolve. Show your work.
18 Juan is g years old and Eva is 2 years younger than Juan.
a) Find the sum of their ages in terms of g.
b) Find the sum of their ages in g years’ time, in terms of g.
36 Chapter 7 Algebraic Expressions
Chapter Wrap UpConcept Map
are combined
and simplified
to form
can be
translated to
can be
Algebraic Expressions
Numbers
(coefficients)
Real-lifesituations
(in word problems)
Operational signs
1, 2, 3, 4
Variables
Evaluated FactoredExpanded
Key Concepts
A letter or variable in an algebraic expression represents an unknown specific
number or any number.
The expression x 1 x 1 x 1 x… (20 terms) is equivalent to 20x.
Expanding and factoring are inverse operations.
10 advanced proofs not final pages
Text
Applying Concepts and SkillsBuilds Real-World Problem Solvers
Frequent ExposureMath in Focus embeds problem solving throughout the lessons.
Learn elements use models to explain computation concepts. students become accustomed to seeing and using visual models to form mental images of mathematical ideas.
17Lesson 7.3 Simplifying Algebraic Expressions
Le
arn Like terms can be subtracted.
a) Simplify 2v 2 v.
2v
v v
2v 2 v 5 v
b) Simplify 5w 2 3w.
5w
3w
w ww w w
5w 2 3w 5 2w
c) Simplify y 2 y.
y 2 y 5 0
2v 2 v and v are equivalent
expressions because they are
equal for all values of v.
If v 5 2, 2v 2 v 5 2 and v 5 2.
If v 5 3, 2v 2 v 5 3 and v 5 3.
Math Note
Any term that is subtracted from
itself is equal to zero.
Guided PracticeComplete.
16 Simplify 4s 2 s.
s ss s
?
?
4s 2 s 5 ?
Simplify each expression.
17 12z 2 7z 18 3p 2 3p
State whether each pair of expressions are equivalent.
19 f 2 6 and 6 2 f 20 5c 2 5c and a 2 a
Model-Drawing Strategiesstudents become familiar with this systematic way to translate complex word problems into mathematical equations, and avoid the common issue of not knowing where to start.
Model Drawing:• helpsstudentssolvesimple
and complex word problems
• developsalgebraicthinking
• followstheintroductionof operational skills
• helpsvisualizethealgebraic structure of the problem
• developsoperationalsense
• fostersproportionalreasoning
16 Chapter 7 Algebraic Expressions
Le
arn Like terms can be added.
a) Simplify 3x 1 x.
3x x
x xx x
3x 1 x 5 x 1 x 1 x 1 x 5 4x
3x and x are the terms of the expression 3x 1 x.
3x and x are called like terms.
In the expression 2y 1 4y 1 6 1 3, 2y and 4y are
like terms. So are 6 and 3.
b) Simplify 4z 1 2z.
4z 2z
z zz z z z
4z 1 2z 5 z 1 z 1 z 1 z 1 z 1 z 5 6z
3x 1 x and 4x are equivalent
expressions because they are
equal for all values of x.
If x 5 1, 3x 1 x 5 4 and 4x 5 4.
If x 5 2, 3x 1 x 5 8 and 4x 5 8.
Guided PracticeComplete.
7 Simplify x 1 8x.
x 1 8x 5 ?
Simplify each expression.
8 3r 1 2r 9 5y 1 6y
State whether each pair of expressions are equivalent.
10 3a and a 1 a 1 a 11 2h 1 2h and 4h
12 2k 1 5 and (k 1 k) 3 5 13 6z 1 4z and 10 1 2z
14 1p 1 3p and 13p 15 3n 1 2 1 4n and 2 1 7n
x x x xx xx x x
? ?
4 Chapter 7 Algebraic Expressions
Le
arn
7.1 Writing Algebraic Expressions
Vocabularyvariable
algebraic expression
terms
Lesson Objective• Usevariablestowritealgebraicexpressions.
A variable can be
replaced by different
values. x is a variable,
so it can represent
different values.
If the length of the first
ribbon is 12 in., then
x is 12.
You can use a letter, called
a variable, to represent
the unknown length.
Use variables to represent unknown numbers and write addition expressions.
a) A 5-inch ribbon is taped to an 8-inch ribbon. What is the total length of the
two ribbons?
?
8 in.5 in.
5 1 8 5 13
The total length of the two ribbons is 13 inches.
b) A ribbon of unknown length is taped to a 9-inch ribbon. What is the total length
of the two ribbons?
Let the length of the first ribbon be x inches.
?
9 in.x in.
12 Chapter 7 Algebraic Expressions
Le
arn
7.3 Simplifying Algebraic Expressions
Lesson Objectives• Simplifyalgebraicexpressionsinonevariable.
• Recognizethattheexpressionobtainedafter
simplifying is equivalent to the original expression.
4 4
4 1 4 5 2 3 4
5 5
5 1 5 5 2 3 5
y y
y 1 y 5 2 3 y
2 3 y is the same as 2y.
p cm p cm
p cm
Algebraic expressions can be simplified.
a) A straw of length y inches is joined to another straw of the same length. What is
the total length of the two straws?
?
y in. y in.
The total length of the two straws is (y 1 y) inches.
y 1 y 5 2 3 y 5 2y y 1 y has been simplified to 2y.
In the term 2y, 2 is called the coefficient of y.
b) Each side of the triangle below has length p centimeters.
Find the perimeter of the triangle in terms of p. Then state the coefficient of the
variable.
Vocabularysimplify
like terms
coefficient
equivalent expressions
Instructional Pathway (CoNTINuED)
11advanced proofs not final pages
34 Chapter 7 Algebraic Expressions
Practice 7.5
1 Jenny is x years old. Thomas is 3 times as old as she is. Jenny is 5 years older
than Alexis.
a) Find Alexis’s age in terms of x.
b) Find Thomas’s age in terms of x.
c) If x 5 12, how much older is Thomas than Jenny?
2 A van travels from Town A to Town B. It uses 1 gallon of gas for every 24 miles
traveled.
a) How many gallons of gas does the van use if it travels 3x miles?
b) The van uses 2y gallons of gas for its journey from Town A to Town B.
Find the distance between Town A and Town B.
3 Brian bought x apples and some oranges. Brian bought 3 more oranges
than apples.
a) Find the total number of fruits Brian bought in terms of x.
b) Find the total amount of money, in cents, that Brian spent on the fruits.
Give your answer in terms of x.
c) If Brian could have bought exactly 12 pears with the amount of money
that was spent on the apples and oranges, find the cost of each pear,
in cents, in terms of x.
4 A rectangle has a width of x centimeters and a perimeter of 8x centimeters.
A square has sides of length 14
that of the length of the rectangle.
a) Find the length of the rectangle.
b) Find the perimeter of the square.
c) Find the difference between the perimeter of the square and the
perimeter of the rectangle if x 5 4.
d) Find the difference between the area of the rectangle and the area of
the square if x 5 4.
Challenging Problemseach Math in Focus chapter concludes with Brain at Work which challenges students to solve non-routine questions.
These problems ask children to draw on deep prior knowledge, as well as recently acquired concepts, combining problem solving strategies with critical thinking skills.
critical thinking skills students develop with Math in Focus include:
• classifying
• comparing
• sequencing
• analyzing
• identifyingpatternsand relationships
• induction(fromspecifictogeneral)
• deduction(fromgeneraltospecific)
• spatialvisualization
Frequent PracticePractice opportunities include both computation and problem solving sections.
• Eachsetofproblemsencompasses previous skills and concepts.
• Wordproblemsgrowincomplexity from 1-step to 2-step to multi-step.
• TheTeacher’sEditionlevelsandlabelsthe problems as Basic, intermediate, and advanced for differentiated instruction.
27Lesson 7.4 Expanding and Factoring Algebraic Expressions
Expand each expression.
1 5(x 1 2) 2 7(2x 2 3)
3 4( y 2 3) 4 8(3y 2 4)
5 3(x 1 11) 6 9(4x 2 7)
Factor each expression.
7 6p 1 6 8 3p 1 18
9 12 1 3q 10 4w 2 16
11 14r 2 8 12 12r 2 12
State whether each pair of expressions are equivalent.
13 4x 1 12 and 4(x 1 3) 14 5(x 2 1) and 5x 2 1
15 7(5 1 y) and 7y 1 35 16 9( y 2 2) and 18 2 9y
Expand each expression.
17 3(m 1 2) 1 4(6 1 m)
18 5(2p 1 5) 1 4(2p 2 3)
19 4(6k 1 7) 1 9 2 14k
Simplify each expression. Then factor the expression.
20 14x 1 13 2 8x 2 1
21 8( y 1 3) 1 6 2 3y
22 4( 3z 1 7) 1 5(8 1 6z)
Solve.
23 Expand and simplify the expression 3(x 2 2) 1 9(x 1 1) 1 5(1 1 2x) 1 2(3x 2 4).
Practice 7.4
8 Chapter 7 Algebraic Expressions
Write an algebraic expression for each of the following.
1 The sum of 4 and p. 2 The difference of q and 8.
3 The product of 3 and r. 4 The quotient of s and 5.
5 Cheryl is now x years old.
a) Her father is 24 years older than Cheryl. Find her father’s age in terms of x.
b) Her brother is 2 years younger than Cheryl. Find her brother’s age in terms of x.
c) Her sister is twice as old as Cheryl. Find her sister’s age in terms of x.
d) Her cousin is 13
Cheryl’s age. Find her cousin’s age in terms of x.
6 Multiply k by 5, and then add 3 to the product.
7 Divide m by 7, and then subtract 4 from the quotient.
8 Divide j by 9, and then multiply the quotient by 2.
9 The sum of 13
of z and 15
of z.
Solve.
10 Jeremy bought 5 pencils for w dollars. Each pen costs 35¢ more than a pencil.
Write an algebraic expression for each of the following in terms of w.
a) The cost, in dollars, of a pen.
b) The number of pencils that Jeremy can buy with $20.
11 The figure shown is formed by a rectangle and a square. Express the area of the
figure in terms of x.
x cm
7 cm
3 cm
Practice 7.1
35Lesson 7.5 Real-WorldProblems:AlgebraicExpressions
5 José bought 4 comic books and 2 nonfiction books. The 4 comic books cost
him 8y dollars. If the cost of one nonfiction book is (3 1 7y) dollars more
expensive than the cost of one comic book, find
a) the cost of the 2 nonfiction books in terms of y.
b) the total amount that José spent on the books if y 5 4.
6 Wyatt has (2x 2 1) one-dollar bills and (4x 1 2) five-dollar bills. Susan has
3x dollars more than Wyatt.
a) Find the total amount of money that Wyatt has in terms of x.
b) Find the number of pens that Wyatt can buy if each pen costs 50¢.
c) If x 5 21, find how much money Susan will have now if Wyatt gives her
half the number of five-dollar bills that he has.
Find the perimeter of the figure in terms of x, given that all the angles in the
figure are right angles. If x 5 5.5, evaluate this expression.
16 cm
x cm
x cm
x cm
12 advanced proofs not final pages
CHAPTER
Chapter at a Glance7
CHAPTER OPENERAlgebraic Expressions
Recall Prior Knowledge
LESSON 7.1Writing Algebraic Expressions
Pages 428
LESSON 7.2Evaluating Algebraic Expressions
Pages 9211
LESS
ON
AT
A G
LAN
CE
Pacing 1 day 2 days 1 day
Objectives
Algebraic
expressions can
be used to describe
situations and solve
real-world problems.
• Usevariablestowritealgebraic
expressions.
• Evaluatealgebraicexpressions
for given values of the variable.
Vocabulary
variable
algebraic expression
terms
evaluate
substitute
RE
SOU
RC
ES
Materials
Lesson Resources
Student Book A, pp. 123 Assessments, Chapter 7
Pre-Test
Transition Guide, Course 1, Skills 24226
Student Book A, pp. 428Extra Practice A, Lesson 7.1Reteach A, Lesson 7.1
Student Book A, pp. 9211Extra Practice A, Lesson 7.2Reteach A, Lesson 7.2
Common Core State Standards
6.EE.2a, b Write, read, and evaluate expressions in which letters stand for numbers. Identify parts of an expression using mathematical terms...; 6.EE.6Usevariables...when solving a real-world or mathematical problem...
6.EE.2 Write, read, and evaluate expressions in which letters stand for numbers. 6.EE.2cEvaluateexpressions at specific values of their variables...
GRADE 5 COURSE 1 COURSE 2
• Evaluateexpressionsusing
grouping symbols. (5.OA.1)
• Writeandinterpretnumerical
expressions to record calculations.
(5.OA.2)
• Identifynumericalpatternsand
rules. (5.OA.3)
• Write,read,andevaluatevariable
expressions.(6.EE.2,6.EE.2a,
6.EE.2b,6.EE.2c)
• Usepropertiestogenerateand
identify equivalent expressions.
(6.EE.3,6.EE.4)
• Usevariablestowriteexpressions
when solving real-world or
mathematicalproblems.(6.EE.6)
• Applypropertiesofoperationsto
add, subtract, factor, expand, and
rewritelinearexpressions.(7.EE.1,
7.EE.2)
• Usealgebraicexpressionstosolve
multi-step problems with rational
numbers.(7.EE.3)
• Usevariablestorepresent
quantities in real-world or
mathematicalproblems.(7.EE.4)
Concepts and Skills Across the Courses
1A Chapter 7 Chapter at a Glance1BChapter 7 Chapter at a Glance
LESSON 7.3Simplifying Algebraic Expressions
Pages 12221
LESSON 7.4Expanding and Factoring
Algebraic ExpressionsPages 22228
LESSON 7.5Real-Word Problems: Algebraic Expressions
Pages 29235
3 days 2 days 2 days
• Simplifyalgebraicexpressionsinone variable.
• Recognizethattheexpressionobtained after simplifying is equivalent to the original expression.
• Expandsimplealgebraicexpressions.
• Factorsimplealgebraicexpressions.
• Solvereal-worldproblemsinvolvingalgebraic expressions.
simplifycoefficientlike termsequivalent expressions
expandfactor
paper,ruler,scissors,TR14* paper, ruler, scissors, yardsticks
Student Book A, pp. 12221Extra Practice A, Lesson 7.3Reteach A, Lesson 7.3
Student Book A, pp. 22228Extra Practice A, Lesson 7.4Reteach A, Lesson 7.4
Student Book A, pp. 29235Extra Practice A, Lesson 7.5Reteach A, Lesson 7.5
6.EE.3 Apply the properties of operations to generate equivalent expressions. 6.EE.4 Identify when two expressions are equivalent. 6.EE.6 Usevariables...whensolvingareal-world or mathematical problem...
6.EE.2 Write, read, and evaluate expressions in which letters stand for numbers. 6.EE.3 Apply the properties of operations to generate equivalent expressions. 6.EE.4 Identify when two expressions are equivalent...
6.EE.6Usevariablestorepresentnumbers and write expressions when solving a real-world or mathematical problem; understand that a variable can represent an unknown number, or, depending on the purpose at hand, any number in a specified set.
TECHNOLOGYEvery Day CountsTM
ALGEBRA READINESS
• OnlineStudenteBook
• Virtual Manipulatives
• TeacherOneStopCD-ROM
• ExamViewAssessmentSuiteCD-ROMCourse 1
• OnlineProfessionalDevelopmentVideos
The January activities in the Pacing Chart provide:
• Review of factors, square numbers, number sequences,
and divisibility (Ch1: 6.NS.4)
• Review of integers and other rational numbers including
decimals, fractions, and percents (Ch224, 6: 6.NS.5,
6.NS.6)
• Preview of patterns and attributes in quadrilaterals
(Ch10: 6.G.3)
• Preview of data collection and analysis and statistical
terms (Ch13214: 6.SP.1, 6.SP.2)
Additional Chapter Resources
PR
OFESSIONAL
LEARNING
*Teacher resources (TR) are available on the Teacher One Stop CD-ROM.
Extensive Teacher Support
Step-by-Step Supportand Embedded Professional DevelopmentMath in Focus Teacher’s Editions provide comprehensive lesson plans with pacing suggestions, step-by-step instructional support, and embedded professional development, including math background discussions and classroom management tips.
skills Trace shows concepts and skills learned in the previous level on which the chapter is based, as well as concepts and skills in the following level to which the chapter will lead. This shows the vertical skills alignment across the three-course series.
every Day Counts® Algebra readiness is an interactive companion piece that encourages classroom discussion through all the strands, with a particular focus on algebraic thinking and reasoning.
Grades 1–5
13advanced proofs not final pages
Chapter 7 Math Background1E
• Similarly,inearliergrades,studentusedbarmodels
torepresentdivisionproblems.Forinstance,students
can use either of the models below to represent the
division probem 36 3.
36
?
? groups
36
3 3 3 3
• Nowstudentswilllearntousebarmodelstosolve
algebraic problems such as the following.
Ericaearnedx dollars in 3 days. If she earned the
same amount each day, how many dollars did she
earn each day?
Solution
x
1 day 1 day 1 day
?
Again, the bar model looks the same; only the labels
havechanged.Fromthemodel,youcan
seethatEricaearnedx3 dollars each day.
Recognizing equivalent expressions• Studentsusebarmodelstorecognizeequivalent
expressions.
Simplify x 1 3x.
3xx
?
x 1 3x 5 4x
PR
OFESSIONAL
LEARNING Math Background
Expanding algebraic expressions• Studentsusebarmodelsandnumberpropertiesto
expand algebraic expressions.
Expand3(p 1 2).
p 2 p 2 p 2
1 group
Rearrangetocollectliketerms.
p p p 2 2 2
3 3 p 3 3 2
3(p 1 2) 5 3 3 ( p 1 2)
5 3 3 p 1 3 3 2
5 3p 1 6
Solving real-world problems• Finally,studentsusebarmodelsandalgebraic
expressions to represent and solve real-world problems.
Jeff is x years old. His sister Sara is 3 years older and
hisbrotherRafaelis2yearsyounger.Writealgebraic
expressionsforSaraandRafael’sages.
x
x
3 2
?
?
Sara: x 13 Rafael:x 2 2
• Usingbarmodelscanhelpstudentssetupexpressions,
so that they can then evaluate them for a given value of
thevariable.Forexample:
IfJeffis10yearsold,howoldareSaraandRafael?
Solution Evaluatetheexpressionsabove.
Sara: x 1 3 5 10 1 3
5 13
Rafael: x 2 2 5 10 2 2
5 8
Algebraic Twists to Familiar Ideas • Inthischapter,studentswilllearnhowtowrite
algebraic expressions to represent situations in
the world around them. Algebraic expressions are
sometimes called variable expressions because they
contain one or more variables.
New algebraic notation• Studentslearntousevariablestorepresentunknown
quantities. They learn to write “6 2 n” to represent
“6 minus a number.”
• Studentslearntocorrectlyidentifytermsinalgebraic
expressions.Forexample,thetermsin3x 1 5 are 3x
and 5.
Working with algebraic expressions• Studentslearnhowtoevaluatealgebraicexpressions
for given values. Asked to evaluate 2x 1 5 for x 5 4,
they substitute 4 for x in the expression, then simplify
to find the value.
2(4) 1 5 5 8 1 5 5 13
• Studentssimplifyalgebraicexpressionsandexpand
and factor them, such as 4(p 2 3) 5 4p 2 12.
• Studentsrecognizeequivalentalgebraicexpressions,
such as 3(x 1 2) 5 3x 1 6.
• Studentssolvereal-worldproblemsusingalgebraic
expressions.
Sarahas3packsofbatteries.Eachpackhasn
batteries. She also has 2 single batteries. How many
batteries does she have in all? Write an expression
to represent the number of batteries Sara has.
3n 1 2
If the packs have 4 batteries each, how many
batteries does she have?
3(4) 1 2 5 12 1 2 5 14
Chapter 7 Algebraic Expressions
PR
OFESSIONAL
LEARNING Math Background
Bar Models • Inthischapter,studentswillrelatewhattheyknow
about bar models to algebraic expressions. The part-
part-whole model was used in earlier grades to solve
problems such as the following:
Peter bought 3 identical packs of baseball cards.
He gave 5 cards away. This left Peter with 31 cards.
How many cards were in each pack?
Solution Draw1longbaranddivideitinto3equalparts.This
represents the identical, full packs of baseball cards.
Sub-divide one of the parts and add the labels 31
and 5 in the model.
31 5
?
FromthemodelyoucanseethatPeterstartedwith
31 1 5 5 36 cards, so each pack had 36 3 5
12 cards.
• Nowstudentswillsolvesimilarproblems,suchasthis:
Peterbought3packsofbaseballcards.Eachpack
had c cards. Then Peter gave 5 cards away. Write
an expression to represent the number of cards
Peter has left.
Solution The bar model looks the same; only the labels have
changed.Fromthemodelyoucanseethathehad
c 1 c 1 (c 2 5) cards left.
c c
31 5
? c
1DChapter 7 Math Background
Additional Teaching Support
Transition Guide, Course 1Online Professional DevelopmentVideos
Continued on next page
1FChapter 7 DifferentiatedInstruction
ASSESSMENT1
2
3
Response to InterventionSTRUGGLING LEARNERS
DIAGNOSTIC• QuickCheckinRecallPriorKnowledge
in Student Book A, pp. 223
• Chapter7Pre-Testin Assessments
• Skills24–26inTransition Guide, Course 1
ON-GOING• GuidedPractice
• LessonCheck
• TicketOuttheDoor
• Reteachworksheets
• ExtraPracticeworksheets
• ActivitiesinActivity Book, Chapter 7
END-OF-CHAPTER
• ChapterReview/Test
• Chapter7TestinAssessments • ExamViewAssessmentSuite
CD-ROMCourse1
• Reteachworksheets
Assessment and Intervention
ADVANCED LEARNERS
• Studentscanbuildvisualpatternsfromanysetof
identical building blocks, toothpicks, grid paper, or
dotpaper.Forexample,studentscouldusebuilding
blocks to build perfect cubes or dot paper to form a
sequence of triangular numbers.
• Havethemlisttermsintheirpatternsandwrite
expressions for the nth term in their patterns. They
may need help in writing expressions for complex
patterns.
• Patternsintwocolorscanbeusedtowrite
expressions for each color, and then for the two colors
combined as an application of combining like terms.
To provide additional challenges use:
• Enrichment, Chapter 7
• StudentBookA,Brain@Workproblem
ELL ENGLISH LANGUAGE LEARNERS
Reviewthetermsvariable, algebraic expression,
and bar model.
Say You can use the letter n to stand for a number you
do not know. The letter n is called a variable. (Write
n 1 2 on the board.) This expression contains a variable
and a number. It is called an algebraic expression.
ModelDrawabarmodeltoshowthealgebraic
expression.
2
?
n
Fordefinitions,seeGlossaryattheendofStudentBook.
Online Multi-Lingual Glossary.
Differentiated Instruction
Differentiated Instruction opportunities are called out for struggling learners, english language learners, and advanced learners.
Math Background clearly outlines the mathematical significance of key concepts. This is embedded professional development for teachers.
Built-in Assessment resources
14 advanced proofs not final pages
4 Chapter 7 Algebraic Expressions
Finding common factors and greatest common factor of two whole numbers
List the common factors of 6 and 14. Then find their greatest common factor.
6 5 1 3 6 14 5 1 3 14
5 2 3 3 5 2 3 7
Factors of 6: 1, 2, 3, 6
Factors of 14: 1, 2, 7, 14
The common factors of 6 and 14 are 1 and 2.
The greatest common factor of 6 and 14 is 2.
Quick CheckFind the common factors and greatest common factor of each pair of numbers.
5 6 and 9 6 4 and 12
7 5 and 15 8 8 and 28
Meaning of mathematical terms
The sum of 3 and 4 is 3 1 4.
The difference of 4 and 3 is 4 2 3.
The product of 3 and 4 is 3 3 4.
The quotient of 3 and 4 is 3 4 4 or 34
. 3 is the dividend and 4 is the divisor.
Quick CheckComplete with quotient, sum, difference, product, dividend, or divisor.
9 The ? of 7 and 5 is 7 2 5.
10 The ? of 5 and 7 is 57
. 7 is the ? and 5 is the ? .
11 The ? of 5 and 7 is 7 3 5.
12 The ? of 5 and 7 is 5 1 7.
1 and 3; 3
1 and 5; 5 1, 2, and 4; 4
1, 2, and 4; 4
difference
quotient; divisor; dividend
product
sum
?
5 ?
?
15 4
17
9?
Recall Prior Knowledge
Quick Check
1 2
3 4
3Chapter 7 AlgebraicExpressions
1
2
3
Response to Intervention ASSESSING PRIOR KNOWLEDGE
Foradditionalassessmentof
students’priorknowledgeand
chapter readiness, use the
Chapter 7 Pre-Test in
Assessments, Course 1.
Response to Intervention Assessing Prior Knowledge
Exercises Skill or Concept Intervene with Transition Guide
1 to 4 Usebarmodelstoshowthefouroperations. Skill 24
5 to 8Findcommonfactorsandthegreatestcommonfactoroftwo
whole numbers.Skill 25
9 to 12 Understandthemeaningofmathematicalterms. Skill 26
4 Chapter 7 Algebraic Expressions
Finding common factors and greatest common factor of two whole numbers
List the common factors of 6 and 14. Then find their greatest common factor.
6 5 1 3 6 14 5 1 3 14
5 2 3 3 5 2 3 7
Factors of 6: 1, 2, 3, 6
Factors of 14: 1, 2, 7, 14
The common factors of 6 and 14 are 1 and 2.
The greatest common factor of 6 and 14 is 2.
Quick CheckFind the common factors and greatest common factor of each pair of numbers.
5 6 and 9 6 4 and 12
7 5 and 15 8 8 and 28
Meaning of mathematical terms
The sum of 3 and 4 is 3 1 4.
The difference of 4 and 3 is 4 2 3.
The product of 3 and 4 is 3 3 4.
The quotient of 3 and 4 is 3 4 4 or 34
. 3 is the dividend and 4 is the divisor.
Quick CheckComplete with quotient, sum, difference, product, dividend, or divisor.
9 The ? of 7 and 5 is 7 2 5.
10 The ? of 5 and 7 is 57
. 7 is the ? and 5 is the ? .
11 The ? of 5 and 7 is 7 3 5.
12 The ? of 5 and 7 is 5 1 7.
1 and 3; 3
1 and 5; 5 1, 2, and 4; 4
1, 2, and 4; 4
difference
quotient; divisor; dividend
product
sum
?
5 ?
?
15 4
17
9?
Recall Prior Knowledge
Quick Check
1 2
3 4
2 Chapter 7 AlgebraicExpressions
RECALL PRIOR KNOWLEDGE
Usethe Quick Checkexercisesasadiagnostictooltoassessstudents’levelofprerequisiteknowledgebeforetheyprogresstothechapter.Forintervention
suggestions see the chart on the next page.
Chapter Vocabulary
factor To write an expression that does not use parentheses as an equivalent expression with parentheses.Forexample, 4x 1 4 5 4(x 1 1).
like terms Terms that have the same variables with the same corresponding exponents. In the expression 2x 1 4 1 x 1 1, the terms 2x and x are like terms, as are 4 and 1.
simplify To write an equivalent expression by combining like terms.
substitute To replace the variable by a number.
term A number, variable, product or quotient found in an expression. In the expression 5x 1 3, the terms are 5x and 3.
variable A quantity represented by a letter that can take different values. In the expression 2x 1 1, x is the variable.
Le
arn
7.1 Writing Algebraic Expressions
Vocabulary
b)
6 Chapter 7 Algebraic Expressions
Le
arn Use variables to write subtraction expressions.
a) A straw of length 10 centimeters is cut from a straw of length 24 centimeters.
What is the length of the remaining straw?
24 cm
10 cm?
24 2 10 5 14
The length of the remaining straw is 14 centimeters.
b) A straw of length 6 centimeters is cut from a straw of length y centimeters. What
is the length of the remaining straw?
? 6 cm
y cm
The length of the remaining straw is ( y 2 6) centimeters.
y 2 6 is an algebraic expression in terms of y.
The total length of the two ribbons is (x 1 9) inches.
x 1 9 is an algebraic expression in terms of x.
x and 9 are the terms of this expression.
You can say that
x 1 9 is the sum
of x and 9.
y and 6 are the terms of the
expression y 2 6.
You can say that y 2 6 is the
difference of y and 6.
5Lesson 7.1 WritingAlgebraicExpressions
ELL Vocabulary Highlight
Remindstudentsthat51 2 and
9 26areexpressions.Reinforce
that the term algebraic means
that one of the terms in the
expression must be a variable
term.
CautionExplaintostudentsthatterms
can be written in any order in an
expression using addition without
affecting the sum. However, the
order of the terms in algebraic
expressions using subtraction is
important. A straw of length
6 centimeters cut from a straw of
length y centimeters can be only
be written as y 2 6, not 6 2 y.
Usethenumericalexampleinpart a to introduce the algebraic
example in part b.
b) Explain In part a, you used a model to show the subtraction
24–10.Nowsupposeyouhadastrawoflengthy centimeters.
Ask How can you show the subtraction of 6 centimeters from
y centimeters? Drawabary cm long and mark off 6 cm. How do
you write the length remaining after 6 centimeters are subtracted?
( y 2 6) cm
Explain Point out that parentheses are used in ( y 26) to indicate
that “centimeters” describes the entire expression, not just the
“6.”
Learn continued
Ask What is the total length of
the two ribbons? (x 1 9) inches
Explain Tell students that x 1 9
is called an algebraic expression
in terms of x. In the expression
x 1 9, the variable x and the
number 9 are called the terms of
the expression. The expression
x 1 9 has two terms, x and 9.
Ask What are the terms in the
expression x 1 4? x and 4
Learn
Use variables to write subtraction expressions.
definitions of key chapter Vocabulary are available for easy reference.
each chapter begins with a day of guiding students to recall Prior Knowledge and a quick check to assess students’ readiness to proceed.
Extensive Teacher Support (CoNTINuED)
Modeled dialogues are included for communication and discussion during instruction.
Grades 1–5
15advanced proofs not final pages
12 Chapter 7 Algebraic Expressions
Evaluate each expression for the given value of the variable.
1 x 1 x 1 5 when x 5 7 2 3x 1 5 when x 5 5
3 5y 2 8 when y 5 3 4 40 2 9y when y 5 2
5 33 2 7w 1 6 when w 5 4 6 76w when w 5 18
7 4 1 56z
when z 5 12 8 4 56
1 z when z 5 12
9 20 2 45r when r 5 10 10 8
9r 2 15 when r 5 27
11 16 2 2 43
z 2 when z 5 18 12 16 2 23z 2 4 when z 5 18
Evaluate each expression when x 5 3.
13 x 1 12
1 5 310
x 2 14 1121 x 2 9 3
4x 2
15 7 63
x 2 1 4(8 1 2x) 16 13(11 2 3x) 2 5 16 42
( )2 x
17 5(x 1 2) 1 2(6 2 x) 1 2 33
x 1 18 5 3
4x 2 1 5 5
8( )x 1 1 3(13 2 2x)
19 2 4
5x 1 2
x 1 14
1 x6
20 7x 2 x5
1 7
92 x
Evaluate each of the following when y 5 7.
21 The difference of (5y 1 2) and (2y 1 5).
22 The sum of y3
and 49y .
23 The product of ( y 1 1) and ( y 2 1).
24 The difference of 8(2y 2 1) and 14 375
y 1 .
25 The quotient of 9(7y 2 15) and 110 642 y .
26 The sum of 56y and 4
37
2y y1
.
27 The quotient of y y2
23
1
and
56 3y y
2
.
Practice 7.2
12
Basic 1 – 12
Intermediate 13 – 20
Advanced 21 – 27
19 20
7 22
11 21
14
12
1
9
0
34 29
61 16
18
48
77
13845
20
49
5
13
2
56
73
23
10
18
135
153
11Lesson 7.2 EvaluatingAlgebraicExpressions
Practice 7.2
Assignment GuideAll students should complete
1 – 20 .
21 – 28 provide additional
challenge.
Optional: Extra Practice 7.2
Write two algebraic expressions
using x that when evaluated for
x 5 3 give the same value. Show
your work. Possible answer:
3x 1 2 and 2x 1 5. When
evaluated for x 5 3,
3x 1 2 5 3(3) 1 2 5 9 1 2 5 11
2x 1 5 5 2(3) 1 5 5 6 1 5 5 11
Also available on
TeacherOneStopCD-ROM.
Response to Intervention Lesson Check
Before assigning homework, use the following … to make sure students … Intervene with …
Exercises 1 , 3 and 11• can evaluate simple algebraic expressions in
one variableReteach7.2
• can write and evaluate simple algebraic
expressions
In 23 , students can write the
product of ( y + 1) and ( y − 1)
before evaluating. Some students
may run into difficulties if they
try to find the product before
evaluating inside parentheses.
Best Practices
Best Practices are highlighted throughout the Teacher’s edition.
Ticket out the Door activities check for understanding at the end of the class period.
Key Concepts
Chapter Wrap UpConcept Map
Algebraic Expressions
38 Chapter 7 Algebraic Expressions
Chapter Review/TestConcepts and SkillsWrite an algebraic expression for each of the following.
1 A number that is 5 more than twice x.
2 The total cost, in dollars, of 4 pencils and 5 pens if each pencil costs w cents
and each pen costs 2w cents.
3 The length of a side of a square whose perimeter is r units.
4 The perimeter of a rectangle whose sides are of lengths (3z 1 2) units and
(2z 1 3) units.
Evaluate each expression for the given value of the variable.
5 3(x 1 4) 2 x2
when x 5 2 6 5 9
2p 1
1 2 5
3p 1
when p 5 5
Simplify each expression.
7 24k 1 11 2 5k 2 4 8 10 1 13h 2 6 2 4h 1 9 1 12h
Expand each expression.
9 5(m 1 3) 1 2(m 1 8) 10 9(x 1 2) 1 4(5 1 x)
Factor each expression.
11 5a 2 25 12 28 2 7x 13 12z 1 28 2 7z 2 3
State whether each pair of expressions are equivalent.
14 3(x 1 5) and 5(x 1 3) 15 6y 2 26 and 2(3y 2 13)
16 18 2 12p and 3(5 1 6p) 1 3(2p 1 1) 17 15 2 5q and 5(q 2 3 )
Problem SolvingSolve. Show your work.
18 Juan is g years old and Eva is 2 years younger than Juan.
a) Find the sum of their ages in terms of g.
b) Find the sum of their ages in g years’ time, in terms of g.
2x 1 5
(10z 1 10) units
7m 1 31
19k 1 7
5(a 2 5) 7(4 2 x) 5(z 1 5)
Equivalent
Not equivalent
Not equivalent
Not equivalent
2g 2 2
4g 2 2
13x 1 38
13 1 21h
17 22
7w50
dollarsr4
units
37Chapter 7 AlgebraicExpressions
TEST PREPARATION
Foradditionaltestprep
Examview Assessment Suite
CD-ROM Course 1
CHAPTER REVIEW/TEST
Chapter Assessment
UsetheChapter7Testin
Assessments, Course 1 to assess
how well students have learned
the material in this chapter. This
assessment is appropriate for
reporting results to adults at
home and administrators.
Response to Intervention Use the table for reteaching recommendations.
Exercises Intervene with Reteach worksheet…
1 to 4 7.1 Writing algebraic expressions
5 to 6 7.2 Evaluatingalgebraicexpressions
7 to 8 7.3 Simplifying algebraic expressions
9 to 17 7.4 Expandingandfactoringalgebraicexpressions
18 to 24 7.5 Solving real-world problems involving algebraic expressions
each chapter ends with a chapter review and a comprehensive assessment. additional test preparation opportunities are referenced in the Teacher’s edition for students who need extra support.
16 advanced proofs not final pages
Transition Support
Transition Guide and online Transition resource Mapfor Program Implementation Grades 6–8The Math in Focus Transition Guide provides a map for teachers and math supervisors to help transition students into the Math in Focus program.
Math BackgroundWithin the Transition Guide and Teacher’s edition, educators will find background information on important concepts covered in the program. The mathematics Background topics were chosen because of their uniqueness to Math in Focus and singapore math. Teachers can use the mathematics Backgrounds within the Transition Guide to ensure they understand the strategies used to teach singapore math and can teach and demonstrate them to students who may not have used them in their previous math programs.
Algebratic Twists to Familiar Ideas
Bar Models
Math Background information in the Transition Guide and Teacher’s edition cover concepts that are unique to singapore math, such as bar modeling.
Grades 1–5
17advanced proofs not final pages
Transition WorksheetsFor each skill objective, the Transition Guide includes Transition Worksheet Blackline masters. These pages provide step-by-step instruction, practice, and review. a student can follow the steps independently or with someone’s help. corresponding Teacher Guides provide strategies for teaching, Quick checks, and intervention suggestions.
an online Transition resource Map is also available, which makes it easy to locate and print transition materials. reteach worksheets and extra Practice worksheets from previous grade levels will be available online for further reinforcement and assessment.
recognizing equivalent expressions solving real-World Problems
Math Background information in the Transition Guide ensures that teachers are prepared to teach and demonstrate singapore math strategies to students who may not have used them in their previous math programs.
18 advanced proofs not final pages
Chapter Table of Contents CourSE 1
Chapter 1 Positive numbers and the number line
Chapter 2 negative numbers and the number line
Chapter 3 multiplying and dividing Fractions and decimals
Chapter 4 ratios
Chapter 5 rates and Unit rates
Chapter 6 Percents
Chapter 7* Algebraic Expressions
chapter at a Glance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1a
math Background. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1d
differentiated instruction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1F
recall Prior Knowledge. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
•Usingbarmodelstoshowthefouroperations •Findingcommonfactorsandgreatestcommonfactor
of two whole numbers •Meaningofmathematicalterms
Lesson 7.1* Writing Algebraic Expressions. . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Learn •Usevariablestorepresentunknownnumbersandwrite addition expressions •Usevariablestowritesubtractionexpressions •Usevariablestowritemultiplicationexpressions •Usevariablestowritedivisionexpressions
Lesson 7.2* Evaluating Algebraic Expressions. . . . . . . . . . . . . . . . . . . . . . . . . 9 Learn algebraic expressions can be evaluated for given values of the variable
Lesson 7.3* Simplifying Algebraic Expressions . . . . . . . . . . . . . . . . . . . . . . . 12 Learn •Algebraicexpressionscanbesimplified •Liketermscanbeadded •Liketermscanbesubtracted •Useorderofoperationstosimplifyalgebraicexpressions •Collectliketermstosimplifyalgebraicexpressions Hands-On Activity recognize that simplified expressions are equivalent
18 advanced proofs not final pages
19advanced proofs not final pages
Teacher’s editio
n
Lesson 7.4* expanding and Factoring Algebraic expressions. . . . . . . . . . . . . 22 Learn •Usethedistributivepropertytoexpandalgebraic expressions •Algebraicexpressionscanbefactoredbytakingout a common factor Hands-On Activity recognize that expanded expressions are equivalent
Lesson 7.5* Real-World Problems: Algebraic Expressions. . . . . . . . . . . . . . . 29 Learn •Writeanadditionorsubtractionalgebraicexpression for a real-world problem and evaluate it •Writeamultiplicationordivisionalgebraicexpression for a real-world problem and evaluate it •Writeanalgebraicexpressionusingseveraloperations and evaluate it chapter Wrap Up. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 chapter review/Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Chapter 8 equations and inequalities
Chapter 9 The coordinate Plane
Chapter 10 area of Polygons
Chapter 11 circumference and area of circles
Chapter 12 volume and surface area of solids
Chapter 13 introduction to statistics
Chapter 14 measures of central Tendency
*Chapter 7 included in sampler
20
Chapter overview COUrse 1 • ChapTer 7
advanced proofs not final pages
CHAPTER
Chapter at a Glance7
CHAPTER OPENERAlgebraic Expressions
Recall Prior Knowledge
LESSON 7.1Writing Algebraic Expressions
Pages 428
LESSON 7.2Evaluating Algebraic Expressions
Pages 9211
LESS
ON
AT
A G
LAN
CE
Pacing 1 day 2 days 1 day
Objectives
Algebraic
expressions can
be used to describe
situations and solve
real-world problems.
• Usevariablestowritealgebraic
expressions.
• Evaluatealgebraicexpressions
for given values of the variable.
Vocabulary
variable
algebraic expression
terms
evaluate
substitute
RE
SOU
RC
ES
Materials
Lesson Resources
Student Book A, pp. 123 Assessments, Chapter 7
Pre-Test
Transition Guide, Course 1, Skills 24226
Student Book A, pp. 428Extra Practice A, Lesson 7.1Reteach A, Lesson 7.1
Student Book A, pp. 9211Extra Practice A, Lesson 7.2Reteach A, Lesson 7.2
Common Core State Standards
6.EE.2a, b Write, read, and evaluate expressions in which letters stand for numbers. Identify parts of an expression using mathematical terms...; 6.EE.6Usevariables...when solving a real-world or mathematical problem...
6.EE.2 Write, read, and evaluate expressions in which letters stand for numbers. 6.EE.2cEvaluateexpressions at specific values of their variables...
GRADE 5 COURSE 1 COURSE 2
• Evaluateexpressionsusing
grouping symbols. (5.OA.1)
• Writeandinterpretnumerical
expressions to record calculations.
(5.OA.2)
• Identifynumericalpatternsand
rules. (5.OA.3)
• Write,read,andevaluatevariable
expressions.(6.EE.2,6.EE.2a,
6.EE.2b,6.EE.2c)
• Usepropertiestogenerateand
identify equivalent expressions.
(6.EE.3,6.EE.4)
• Usevariablestowriteexpressions
when solving real-world or
mathematicalproblems.(6.EE.6)
• Applypropertiesofoperationsto
add, subtract, factor, expand, and
rewritelinearexpressions.(7.EE.1,
7.EE.2)
• Usealgebraicexpressionstosolve
multi-step problems with rational
numbers.(7.EE.3)
• Usevariablestorepresent
quantities in real-world or
mathematicalproblems.(7.EE.4)
Concepts and Skills Across the Courses
1A Chapter 7 Chapter at a Glance
21advanced proofs not final pages
Teacher’s editio
n
1BChapter 7 Chapter at a Glance
LESSON 7.3Simplifying Algebraic Expressions
Pages 12221
LESSON 7.4Expanding and Factoring
Algebraic ExpressionsPages 22228
LESSON 7.5Real-Word Problems: Algebraic Expressions
Pages 29235
3 days 2 days 2 days
• Simplifyalgebraicexpressionsinone variable.
• Recognizethattheexpressionobtained after simplifying is equivalent to the original expression.
• Expandsimplealgebraicexpressions.
• Factorsimplealgebraicexpressions.
• Solvereal-worldproblemsinvolvingalgebraic expressions.
simplifycoefficientlike termsequivalent expressions
expandfactor
paper,ruler,scissors,TR14* paper, ruler, scissors, yardsticks
Student Book A, pp. 12221Extra Practice A, Lesson 7.3Reteach A, Lesson 7.3
Student Book A, pp. 22228Extra Practice A, Lesson 7.4Reteach A, Lesson 7.4
Student Book A, pp. 29235Extra Practice A, Lesson 7.5Reteach A, Lesson 7.5
6.EE.3 Apply the properties of operations to generate equivalent expressions. 6.EE.4 Identify when two expressions are equivalent. 6.EE.6 Usevariables...whensolvingareal-world or mathematical problem...
6.EE.2 Write, read, and evaluate expressions in which letters stand for numbers. 6.EE.3 Apply the properties of operations to generate equivalent expressions. 6.EE.4 Identify when two expressions are equivalent...
6.EE.6Usevariablestorepresentnumbers and write expressions when solving a real-world or mathematical problem; understand that a variable can represent an unknown number, or, depending on the purpose at hand, any number in a specified set.
TECHNOLOGYEvery Day CountsTM
ALGEBRA READINESS
• OnlineStudenteBook
• Virtual Manipulatives
• TeacherOneStopCD-ROM
• ExamViewAssessmentSuiteCD-ROMCourse 1
• OnlineProfessionalDevelopmentVideos
The January activities in the Pacing Chart provide:
• Review of factors, square numbers, number sequences,
and divisibility (Ch1: 6.NS.4)
• Review of integers and other rational numbers including
decimals, fractions, and percents (Ch224, 6: 6.NS.5,
6.NS.6)
• Preview of patterns and attributes in quadrilaterals
(Ch10: 6.G.3)
• Preview of data collection and analysis and statistical
terms (Ch13214: 6.SP.1, 6.SP.2)
Additional Chapter Resources
PR
OFESSIONAL
LEARNING
*Teacher resources (TR) are available on the Teacher One Stop CD-ROM.
22
Chapter overview COUrse 1 • ChapTer 7
advanced proofs not final pages
CHAPTER
Chapter at a Glance7
Chapter 7 Chapter at a Glance1C
CHAPTERWRAP UP/REVIEW/TEST
Brain@Work Pages 35–38
LESS
ON
AT
A G
LAN
CE
Pacing 1 day
Objectives
Reinforce,consolidate,andextendchapter skills and concepts.
Vocabulary
RE
SOU
RC
ES
Materials
Lesson Resources
Student Book A, pp. 35–38 Activity Book, Chapter 7 Project Enrichment, Chapter 7Assessments, Chapter 7 Test
ExamViewAssessmentSuite CD-ROMCourse1
Common Core State Standards
TEACHER NOTES
23advanced proofs not final pages
Teacher’s editio
n
Algebraic Twists to Familiar Ideas • Inthischapter,studentswilllearnhowtowrite
algebraic expressions to represent situations in
the world around them. Algebraic expressions are
sometimes called variable expressions because they
contain one or more variables.
New algebraic notation• Studentslearntousevariablestorepresentunknown
quantities. They learn to write “6 2 n” to represent
“6 minus a number.”
• Studentslearntocorrectlyidentifytermsinalgebraic
expressions.Forexample,thetermsin3x 1 5 are 3x
and 5.
Working with algebraic expressions• Studentslearnhowtoevaluatealgebraicexpressions
for given values. Asked to evaluate 2x 1 5 for x 5 4,
they substitute 4 for x in the expression, then simplify
to find the value.
2(4) 1 5 5 8 1 5 5 13
• Studentssimplifyalgebraicexpressionsandexpand
and factor them, such as 4(p 2 3) 5 4p 2 12.
• Studentsrecognizeequivalentalgebraicexpressions,
such as 3(x 1 2) 5 3x 1 6.
• Studentssolvereal-worldproblemsusingalgebraic
expressions.
Sarahas3packsofbatteries.Eachpackhasn
batteries. She also has 2 single batteries. How many
batteries does she have in all? Write an expression
to represent the number of batteries Sara has.
3n 1 2
If the packs have 4 batteries each, how many
batteries does she have?
3(4) 1 2 5 12 1 2 5 14
Chapter 7 Algebraic Expressions
PR
OFESSIONAL
LEARNING Math Background
Bar Models • Inthischapter,studentswillrelatewhattheyknow
about bar models to algebraic expressions. The part-
part-whole model was used in earlier grades to solve
problems such as the following:
Peter bought 3 identical packs of baseball cards.
He gave 5 cards away. This left Peter with 31 cards.
How many cards were in each pack?
Solution Draw1longbaranddivideitinto3equalparts.This
represents the identical, full packs of baseball cards.
Sub-divide one of the parts and add the labels 31
and 5 in the model.
31 5
?
FromthemodelyoucanseethatPeterstartedwith
31 1 5 5 36 cards, so each pack had 36 3 5
12 cards.
• Nowstudentswillsolvesimilarproblems,suchasthis:
Peterbought3packsofbaseballcards.Eachpack
had c cards. Then Peter gave 5 cards away. Write
an expression to represent the number of cards
Peter has left.
Solution The bar model looks the same; only the labels have
changed.Fromthemodelyoucanseethathehad
c 1 c 1 (c 2 5) cards left.
c c
31 5
? c
1DChapter 7 Math Background
Additional Teaching Support
Transition Guide, Course 1Online Professional DevelopmentVideos
Continued on next page
24 advanced proofs not final pages
Chapter overview COUrse 1 • ChapTer 7
Chapter 7 Math Background1E
• Similarly,inearliergrades,studentusedbarmodels
torepresentdivisionproblems.Forinstance,students
can use either of the models below to represent the
division probem 36 3.
36
?
? groups
36
3 3 3 3
• Nowstudentswilllearntousebarmodelstosolve
algebraic problems such as the following.
Ericaearnedx dollars in 3 days. If she earned the
same amount each day, how many dollars did she
earn each day?
Solution
x
1 day 1 day 1 day
?
Again, the bar model looks the same; only the labels
havechanged.Fromthemodel,youcan
seethatEricaearnedx3 dollars each day.
Recognizing equivalent expressions• Studentsusebarmodelstorecognizeequivalent
expressions.
Simplify x 1 3x.
3xx
?
x 1 3x 5 4x
PR
OFESSIONAL
LEARNING Math Background
Expanding algebraic expressions• Studentsusebarmodelsandnumberpropertiesto
expand algebraic expressions.
Expand3(p 1 2).
p 2 p 2 p 2
1 group
Rearrangetocollectliketerms.
p p p 2 2 2
3 3 p 3 3 2
3(p 1 2) 5 3 3 ( p 1 2)
5 3 3 p 1 3 3 2
5 3p 1 6
Solving real-world problems• Finally,studentsusebarmodelsandalgebraic
expressions to represent and solve real-world problems.
Jeff is x years old. His sister Sara is 3 years older and
hisbrotherRafaelis2yearsyounger.Writealgebraic
expressionsforSaraandRafael’sages.
x
x
3 2
?
?
Sara: x 13 Rafael:x 2 2
• Usingbarmodelscanhelpstudentssetupexpressions,
so that they can then evaluate them for a given value of
thevariable.Forexample:
IfJeffis10yearsold,howoldareSaraandRafael?
Solution Evaluatetheexpressionsabove.
Sara: x 1 3 5 10 1 3
5 13
Rafael: x 2 2 5 10 2 2
5 8
25advanced proofs not final pages
Teacher’s editio
n
1FChapter 7 DifferentiatedInstruction
ASSESSMENT1
2
3
Response to InterventionSTRUGGLING LEARNERS
DIAGNOSTIC• QuickCheckinRecallPriorKnowledge
in Student Book A, pp. 223
• Chapter7Pre-Testin Assessments
• Skills24–26inTransition Guide, Course 1
ON-GOING• GuidedPractice
• LessonCheck
• TicketOuttheDoor
• Reteachworksheets
• ExtraPracticeworksheets
• ActivitiesinActivity Book, Chapter 7
END-OF-CHAPTER
• ChapterReview/Test
• Chapter7TestinAssessments • ExamViewAssessmentSuite
CD-ROMCourse1
• Reteachworksheets
Assessment and Intervention
ADVANCED LEARNERS
• Studentscanbuildvisualpatternsfromanysetof
identical building blocks, toothpicks, grid paper, or
dotpaper.Forexample,studentscouldusebuilding
blocks to build perfect cubes or dot paper to form a
sequence of triangular numbers.
• Havethemlisttermsintheirpatternsandwrite
expressions for the nth term in their patterns. They
may need help in writing expressions for complex
patterns.
• Patternsintwocolorscanbeusedtowrite
expressions for each color, and then for the two colors
combined as an application of combining like terms.
To provide additional challenges use:
• Enrichment, Chapter 7
• StudentBookA,Brain@Workproblem
ELL ENGLISH LANGUAGE LEARNERS
Reviewthetermsvariable, algebraic expression,
and bar model.
Say You can use the letter n to stand for a number you
do not know. The letter n is called a variable. (Write
n 1 2 on the board.) This expression contains a variable
and a number. It is called an algebraic expression.
ModelDrawabarmodeltoshowthealgebraic
expression.
2
?
n
Fordefinitions,seeGlossaryattheendofStudentBook.
Online Multi-Lingual Glossary.
Differentiated Instruction
26
Chapter opener COUrse 1 • ChapTer 7
The following is Chapter 7 Algebraic Expressions from the Math in Focus CourSE 1 Teacher’s Edition
27advanced proofs not final pages
Teacher’s editio
n
2 Chapter 7 Algebraic Expressions
Algebraic Expressions How safe is it?Imagine this: You are standing on a bridge, about to experience the thrill
of bungee jumping. A fast-flowing river rushes by beneath you, and a
bungee cord is strapped around your ankles. How safe is it for you to
make the jump? Is the bungee cord the right length?
To answer this question, you can use an algebraic expression to calculate
how much the bungee cord will stretch when you jump. For example,
the amount the cord stretches is 80.9 feet for a 100-pound person, and
111.5 feet for a 150-pound person.
In this chapter, you will learn how variables and algebraic expressions
can be used in daily life. For example, the manufacturer of the bungee
cords uses an algebraic expression to find the weights that are safe
for jumping.
BIG IDEA
CHAPTER
7
7.1 Writing Algebraic Expressions
7.2 Evaluating Algebraic Expressions
7.3 Simplifying Algebraic Expressions
7.4 Expanding and Factoring Algebraic Expressions
Algebraic expressions can be used to describe situations and solve real-world problems.
7.5 Real-World Problems: Algebraic Expressions
1Chapter 7 AlgebraicExpressions
CHAPTER OPENER
Usethechapteropenertotalkabouttheuseofalgebrain
a real life situation.
Ask Has anyone ever watched bungee jumping? What
makes the cord stretch when a person jumps? Possible
answer: The weight of the person pulls down on the cord,
causing it to stretch.
Explain The extension in the bungee cord can be
calculated using algebra. By substituting different values of
aperson’sweightintothealgebraicformulaforcalculating
the extension, the heaviest weight that the cord can safely
takecanbeevaluated.Forsafetyreasons,ajumper’s
weight must be less than this weight.
In this chapter, you will learn how to write and evaluate
algebraic expressions for many different situations, as
summarizedintheBig Idea.
Chapter Vocabulary
Vocabulary terms are used in context inthestudenttext.Fordefinitions,see the Glossary at the end of the Student Book and the online Multi-Lingual Glossary.
algebraic expression An expression that contains at least one variable.
3y 2 2 and y4
are algebraic
expressions.
coefficient The numerical factor in a term of an algebraic expression. In the term 8z, the coefficient of z is 8.
equivalent expressionsExpressionsthat are equal for all values of the variables. 2x 1 x and 3x are equivalent expressions because 2x 1 x 5 3x for all values of x.
evaluate To find the value.
expand To write an expression that uses parentheses as an equivalent expression without parentheses. Forexample,4(y 1 1) 5 4y 1 4.
CHAPTER
77CHAPTER
28 advanced proofs not final pages
recall Prior Knowledge COUrse 1 • ChapTer 7
4 Chapter 7 Algebraic Expressions
Finding common factors and greatest common factor of two whole numbers
List the common factors of 6 and 14. Then find their greatest common factor.
6 5 1 3 6 14 5 1 3 14
5 2 3 3 5 2 3 7
Factors of 6: 1, 2, 3, 6
Factors of 14: 1, 2, 7, 14
The common factors of 6 and 14 are 1 and 2.
The greatest common factor of 6 and 14 is 2.
Quick CheckFind the common factors and greatest common factor of each pair of numbers.
5 6 and 9 6 4 and 12
7 5 and 15 8 8 and 28
Meaning of mathematical terms
The sum of 3 and 4 is 3 1 4.
The difference of 4 and 3 is 4 2 3.
The product of 3 and 4 is 3 3 4.
The quotient of 3 and 4 is 3 4 4 or 34
. 3 is the dividend and 4 is the divisor.
Quick CheckComplete with quotient, sum, difference, product, dividend, or divisor.
9 The ? of 7 and 5 is 7 2 5.
10 The ? of 5 and 7 is 57
. 7 is the ? and 5 is the ? .
11 The ? of 5 and 7 is 7 3 5.
12 The ? of 5 and 7 is 5 1 7.
1 and 3; 3
1 and 5; 5 1, 2, and 4; 4
1, 2, and 4; 4
difference
quotient; divisor; dividend
product
sum
?
5 ?
?
15 4
17
9?
Recall Prior Knowledge
Quick Check
1 2
3 4
2 Chapter 7 AlgebraicExpressions
RECALL PRIOR KNOWLEDGE
Usethe Quick Checkexercisesasadiagnostictooltoassessstudents’levelofprerequisiteknowledgebeforetheyprogresstothechapter.Forintervention
suggestions see the chart on the next page.
Chapter Vocabulary
factor To write an expression that does not use parentheses as an equivalent expression with parentheses.Forexample, 4x 1 4 5 4(x 1 1).
like terms Terms that have the same variables with the same corresponding exponents. In the expression 2x 1 4 1 x 1 1, the terms 2x and x are like terms, as are 4 and 1.
simplify To write an equivalent expression by combining like terms.
substitute To replace the variable by a number.
term A number, variable, product or quotient found in an expression. In the expression 5x 1 3, the terms are 5x and 3.
variable A quantity represented by a letter that can take different values. In the expression 2x 1 1, x is the variable.
29advanced proofs not final pages
Teacher’s editio
n
4 Chapter 7 Algebraic Expressions
Finding common factors and greatest common factor of two whole numbers
List the common factors of 6 and 14. Then find their greatest common factor.
6 5 1 3 6 14 5 1 3 14
5 2 3 3 5 2 3 7
Factors of 6: 1, 2, 3, 6
Factors of 14: 1, 2, 7, 14
The common factors of 6 and 14 are 1 and 2.
The greatest common factor of 6 and 14 is 2.
Quick CheckFind the common factors and greatest common factor of each pair of numbers.
5 6 and 9 6 4 and 12
7 5 and 15 8 8 and 28
Meaning of mathematical terms
The sum of 3 and 4 is 3 1 4.
The difference of 4 and 3 is 4 2 3.
The product of 3 and 4 is 3 3 4.
The quotient of 3 and 4 is 3 4 4 or 34
. 3 is the dividend and 4 is the divisor.
Quick CheckComplete with quotient, sum, difference, product, dividend, or divisor.
9 The ? of 7 and 5 is 7 2 5.
10 The ? of 5 and 7 is 57
. 7 is the ? and 5 is the ? .
11 The ? of 5 and 7 is 7 3 5.
12 The ? of 5 and 7 is 5 1 7.
1 and 3; 3
1 and 5; 5 1, 2, and 4; 4
1, 2, and 4; 4
difference
quotient; divisor; dividend
product
sum
?
5 ?
?
15 4
17
9?
Recall Prior Knowledge
Quick Check
1 2
3 4
3Chapter 7 AlgebraicExpressions
1
2
3
Response to Intervention ASSESSING PRIOR KNOWLEDGE
Foradditionalassessmentof
students’priorknowledgeand
chapter readiness, use the
Chapter 7 Pre-Test in
Assessments, Course 1.
1
2
3
Response to Intervention Assessing Prior Knowledge
Exercises Skill or Concept Intervene with Transition Guide
1 to 4 Usebarmodelstoshowthefouroperations. Skill 24
5 to 8Findcommonfactorsandthegreatestcommonfactoroftwo
whole numbers.Skill 25
9 to 12 Understandthemeaningofmathematicalterms. Skill 26
30 advanced proofs not final pages
Lesson 1 COUrse 1 • ChapTer 7
Le
arn
7.1 Writing Algebraic Expressions
Vocabulary
b)
6 Chapter 7 Algebraic Expressions
Le
arn Use variables to write subtraction expressions.
a) A straw of length 10 centimeters is cut from a straw of length 24 centimeters.
What is the length of the remaining straw?
24 cm
10 cm?
24 2 10 5 14
The length of the remaining straw is 14 centimeters.
b) A straw of length 6 centimeters is cut from a straw of length y centimeters. What
is the length of the remaining straw?
? 6 cm
y cm
The length of the remaining straw is ( y 2 6) centimeters.
y 2 6 is an algebraic expression in terms of y.
The total length of the two ribbons is (x 1 9) inches.
x 1 9 is an algebraic expression in terms of x.
x and 9 are the terms of this expression.
You can say that
x 1 9 is the sum
of x and 9.
y and 6 are the terms of the
expression y 2 6.
You can say that y 2 6 is the
difference of y and 6.
4 Chapter 7 AlgebraicExpressions
a) Ask How can you find the total length of the two
ribbons? 5 1 8 5 13; 13 inches
Model Remindstudentsthatabarmodelcanbe
used to represent the addition sentence.
b) Ask How do you represent the unknown length of
the ribbon? x
ExplainExplainthatwhentheactualnumberis
not known, you can use a letter to represent this
unknown number. The letter x is called a variable,
because it can take different values depending on
what the actual length of the first ribbon is.
Explain If the length of the first ribbon is 12 in.,
then x 5 12. If the length is 24 in., then x 5 24.
Emphasizethatx represents a number.
KEY CONCEPTS
• Youcanuseavariabletorepresent
an unknown number or numbers.
• Youcanusevariablestowrite
algebraic expressions.
DAY 1
PACING
DAY 1 Pages 425
DAY 2 Pages 628
Materials: none
Learn Use variables to represent unknown numbers and write addition expressions.
Writing Algebraic Expressions7.1
5 5-minute Warm Up
1. John is 12 years old. His sister
is 6 years older.
Ask: How do you find his
sister’sage?Add 6 to 12.
2. Joyce is 15 years old. Her
brother is 4 years younger.
Ask: How do you find her
brother’sage?Subtract 4
from 15.
Also available on
TeacherOneStopCD-ROM.
31advanced proofs not final pages
Teacher’s editio
n
Le
arn
7.1 Writing Algebraic Expressions
Vocabulary
b)
6 Chapter 7 Algebraic Expressions
Le
arn Use variables to write subtraction expressions.
a) A straw of length 10 centimeters is cut from a straw of length 24 centimeters.
What is the length of the remaining straw?
24 cm
10 cm?
24 2 10 5 14
The length of the remaining straw is 14 centimeters.
b) A straw of length 6 centimeters is cut from a straw of length y centimeters. What
is the length of the remaining straw?
? 6 cm
y cm
The length of the remaining straw is ( y 2 6) centimeters.
y 2 6 is an algebraic expression in terms of y.
The total length of the two ribbons is (x 1 9) inches.
x 1 9 is an algebraic expression in terms of x.
x and 9 are the terms of this expression.
You can say that
x 1 9 is the sum
of x and 9.
y and 6 are the terms of the
expression y 2 6.
You can say that y 2 6 is the
difference of y and 6.
5Lesson 7.1 WritingAlgebraicExpressions
ELL Vocabulary Highlight
Remindstudentsthat51 2 and
9 26areexpressions.Reinforce
that the term algebraic means
that one of the terms in the
expression must be a variable
term.
CautionExplaintostudentsthatterms
can be written in any order in an
expression using addition without
affecting the sum. However, the
order of the terms in algebraic
expressions using subtraction is
important. A straw of length
6 centimeters cut from a straw of
length y centimeters can be only
be written as y 2 6, not 6 2 y.
Usethenumericalexampleinpart a to introduce the algebraic
example in part b.
b) Explain In part a, you used a model to show the subtraction
24–10.Nowsupposeyouhadastrawoflengthy centimeters.
Ask How can you show the subtraction of 6 centimeters from
y centimeters? Drawabary cm long and mark off 6 cm. How do
you write the length remaining after 6 centimeters are subtracted?
( y 2 6) cm
Explain Point out that parentheses are used in ( y 26) to indicate
that “centimeters” describes the entire expression, not just the
“6.”
Learn continued
Ask What is the total length of
the two ribbons? (x 1 9) inches
Explain Tell students that x 1 9
is called an algebraic expression
in terms of x. In the expression
x 1 9, the variable x and the
number 9 are called the terms of
the expression. The expression
x 1 9 has two terms, x and 9.
Ask What are the terms in the
expression x 1 4? x and 4
Learn
Use variables to write subtraction expressions.
32 advanced proofs not final pages
Lesson 1 COUrse 1 • ChapTer 7
8 Chapter 7 Algebraic Expressions
Le
arn
?
12 in.
Use variables to write division expressions.
a) A 12-inch rod is divided into 3 parts of equal length.
What is the length of each part?
12 4 3 5 4
The length of each part is 4 inches.
b) A rod of length w inches is divided into 7 parts of equal length. What is the
length of each part?
?
w in.
The length of each part is (w 4 7) inches or w7
inches.
w7
is an algebraic expression in terms of w.
Guided PracticeWrite an algebraic expression for each of the following.
4 The product of z and 6.
5 The quotient of w and 8.
6 Mia bought a pair of shoes for p dollars. She also bought a dress that cost 5 times as
much as the shoes, and a belt that cost 14
of the price of the shoes.
a) Find the cost of the dress in terms of p.
b) Find the cost of the belt in terms of p.
Math Note
w7
can also be written as 17
w.
w7
is the only term of the expression w7
.
You can say that w7
is the quotient of w and 7.
w is the dividend and 7 is the divisor.
6z
5p dollars
, or p dollarsp4
14
w8
7Lesson 7.2 Evaluating Algebraic Expressions
Le
arn
4z is the only term of the
expression 4z.
You can say that 4z is the
product of z and 4.
Use variables to write multiplication expressions.
a) There are 12 crackers in each box. How many crackers are there in 2 boxes?
?
12
2 3 12 5 24
There are 24 crackers in 2 boxes.
b) There are z crackers in each box. How many crackers are there in 4 boxes?
?
z
4 3 z 5 4z There are 4z crackers in 4 boxes.
4z is an algebraic expression in terms of z.
Guided PracticeWrite an algebraic expression for each of the following.
1 The sum of x and 10.
2 The difference of y and 7.
3 Jim is now z years old.
a) His brother is 4 years older than Jim. Find his brother’s age in terms of z.
b) His sister is 3 years younger than Jim. Find his sister’s age in terms of z.
x 1 10
z 1 4
z 2 3
y 2 7
6 Chapter 7 AlgebraicExpressions
Guided Practice 1 and 2 Explaintostudentsthat
the terms sum and difference are
used in the same way with variables
as with numbers.
3 Watch out for students who
may not understand that “4 years
older than” implies addition, and
that “3 years younger than” implies
subtraction.
Learn
a) Ask How many crackers are there in 2 boxes?
2 3 12 5 24
Model Remindstudentsthatabarmodelcanbe
used to represent the multiplication sentence.
b) Ask If there are z crackers in each box, how many
crackers will there be in 4 boxes? 4z How many
terms are in the expression 4z? 1
Ask If there are 5 boxes, what is the total number of
crackers? 5z What will the algebraic expression for the
total number of crackers be if there are 12 boxes? 12z
Explain Tell students that 4z, 5z, and 12z are algebraic
expressions in terms of z.
Ask What are the terms of the expressions 4z, 5z, and
12z? 4z, 5z, and 12z
DAY 2
Use variables to write multiplication expressions.
Point out to students that the
number in a multiplication
expression such as 4x is usually
written in front of the variable.
So, the “product of z and 4” is
written as 4z.
Best Practices
33advanced proofs not final pages
Teacher’s editio
n
8 Chapter 7 Algebraic Expressions
Le
arn
?
12 in.
Use variables to write division expressions.
a) A 12-inch rod is divided into 3 parts of equal length.
What is the length of each part?
12 4 3 5 4
The length of each part is 4 inches.
b) A rod of length w inches is divided into 7 parts of equal length. What is the
length of each part?
?
w in.
The length of each part is (w 4 7) inches or w7
inches.
w7
is an algebraic expression in terms of w.
Guided PracticeWrite an algebraic expression for each of the following.
4 The product of z and 6.
5 The quotient of w and 8.
6 Mia bought a pair of shoes for p dollars. She also bought a dress that cost 5 times as
much as the shoes, and a belt that cost 14
of the price of the shoes.
a) Find the cost of the dress in terms of p.
b) Find the cost of the belt in terms of p.
Math Note
w7
can also be written as 17
w.
w7
is the only term of the expression w7
.
You can say that w7
is the quotient of w and 7.
w is the dividend and 7 is the divisor.
6z
5p dollars
, or p dollarsp4
14
w8
7Lesson 7.2 Evaluating Algebraic Expressions
Le
arn
4z is the only term of the
expression 4z.
You can say that 4z is the
product of z and 4.
Use variables to write multiplication expressions.
a) There are 12 crackers in each box. How many crackers are there in 2 boxes?
?
12
2 3 12 5 24
There are 24 crackers in 2 boxes.
b) There are z crackers in each box. How many crackers are there in 4 boxes?
?
z
4 3 z 5 4z There are 4z crackers in 4 boxes.
4z is an algebraic expression in terms of z.
Guided PracticeWrite an algebraic expression for each of the following.
1 The sum of x and 10.
2 The difference of y and 7.
3 Jim is now z years old.
a) His brother is 4 years older than Jim. Find his brother’s age in terms of z.
b) His sister is 3 years younger than Jim. Find his sister’s age in terms of z.
x 1 10
z 1 4
z 2 3
y 2 7
7Lesson 7.1 WritingAlgebraicExpressions
Guided Practice4 and 5 Explaintostudentsthat
the terms product and quotient are
used in the same way with variables
aswithnumbers.Remindstudents
that 6z means 6 3 z and not six z’s.
Ask students to describe
situations in which they might
have to use division, such as
finding the cost for each friend if
5 friends pay a total of x dollars
for movie tickets. Have them
describe the situation using a
variable and model it with an
algebraic expression.
Best Practices
Learn
a) Ask What is the length of each part of the rod?
12 3 5 4; 4 inches
Model Remindstudentsthatabarmodelcanbeused
to represent the division sentence.
b) Ask If a rod of w inches is divided into 7 parts of equal
length, how can you find the length of each part?
w 7 5 w7
; w7
inches Point out that w7
is
the only term of the expression.
Ask If the rod is divided into 9 parts of equal length,
what will the length of each part be? w9
Use variables to write division expressions.
Explain Tell students that w7
and w9
are algebraic
expressions in terms of w.
Ask What are the terms of the expressions w7
and w9
?w7
and w9
Explain Show students thatw7
5 w 7 5 w 3 17
5 17
3 w 5 17
w.
Point out that the order of the
terms in an algebraic expression
involving multiplication does
not affect the product, but such
expressions are usually written
withthevariablelast.Explain
that the order of the terms in a
division expression does matter. If
a rod of w inches is divided into 7
parts of equal length, the correct
expression is w 7, not 7 w.
Caution
34 advanced proofs not final pages
Lessons 1 and 2 COUrse 1 • ChapTer 7
10 Chapter 7 Algebraic Expressions
Le
arn
7.2 Evaluating Algebraic Expressions
Vocabularyevaluate
substitute
Lesson Objective• Evaluatealgebraicexpressionsforgivenvaluesofthevariable.
Algebraic expressions can be evaluated for given values of the variable.
a) Simon has x marbles and Cynthia has 3 marbles. How many more marbles does
Simon have than Cynthia?
x
?3
Simon
Cynthia
From the model, Simon has (x 2 3) more marbles than Cynthia.
To know exactly how many more marbles Simon has than Cynthia, you need to
know the value of x.
When x 5 5, x 2 3 5 5 2 3
5 2
When x 5 5, Simon has 2 more marbles than Cynthia.
When x 5 9, x 2 3 5 9 2 3
5 6
When x 5 9, Simon has 6 more marbles than Cynthia.
When x 5 17, x 2 3 5 17 2 3
5 14
When x 5 17, Simon has 14 more marbles than Cynthia.
Continue on next page
1 2
3 4
5
a)
13
6
7
8
913
15
a)
11
Practice 7.1
dollarsw5
0 351 .
Basic 1 – 5
Intermediate 6 – 9
Advanced 10 – 11
4 1 p
3r
(7x 1 9) cm2
5k 1 3
x 1 24
2x
x 2 2
q 2 8
s5
x3
2 4m7
3 2j9
z1 z13
15
pencils100w
8 Chapter 7 AlgebraicExpressions
1
2
3
Response to Intervention Lesson Check
Before assigning homework, use the following … to make sure students … Intervene with …
Exercises 1 and 2• can identify and write simple algebraic
expressionsReteach7.1
• can write an algebraic expression to
represent a situation
Practice 7.1
Assignment Guide
DAY 1 All students should
complete 1 – 2 .
DAY 2 All students should
complete 3 – 9 .
10 – 11 provide additional
challenge.
Optional: Extra Practice 7.1
Benis3timesasoldasKyra.Dilip
is4yearsyoungerthanKyra.If
Kyraisx years old, how old is
Ben?HowoldisDilip?Writean
algebraic expression for each
boy’sage.
Ben’sage:3x;Dilip’sage:x 2 3
Also available on
TeacherOneStopCD-ROM.
35advanced proofs not final pages
Teacher’s editio
n
10 Chapter 7 Algebraic Expressions
Le
arn
7.2 Evaluating Algebraic Expressions
Vocabularyevaluate
substitute
Lesson Objective• Evaluatealgebraicexpressionsforgivenvaluesofthevariable.
Algebraic expressions can be evaluated for given values of the variable.
a) Simon has x marbles and Cynthia has 3 marbles. How many more marbles does
Simon have than Cynthia?
x
?3
Simon
Cynthia
From the model, Simon has (x 2 3) more marbles than Cynthia.
To know exactly how many more marbles Simon has than Cynthia, you need to
know the value of x.
When x 5 5, x 2 3 5 5 2 3
5 2
When x 5 5, Simon has 2 more marbles than Cynthia.
When x 5 9, x 2 3 5 9 2 3
5 6
When x 5 9, Simon has 6 more marbles than Cynthia.
When x 5 17, x 2 3 5 17 2 3
5 14
When x 5 17, Simon has 14 more marbles than Cynthia.
Continue on next page
9Lesson 7.2 EvaluatingAlgebraicExpressions
5
KEY CONCEPT
• You can evaluate algebraic
expressions for given values of
the variables.
Evaluating Algebraic Expressions
7.2
5-minute Warm Up
Reviewhowtoevaluatethese
numerical expressions:
1. (3 3 5) 1 8 23
2. 18 2 (4 3 4) 2
3. 15 2 ( )2 6
33
11
4. ( )8 3
43 1
( )22 872
2 186
5
Also available on
TeacherOneStopCD-ROM.
PACING
DAY 1 Pages 9–11
Materials: none
Learn
a) ModelUseabarmodeltoshowthatSimonhas
(x 23)moremarblesthanCynthia.Explainthat,in
order to know exactly how many more marbles, they
need the exact value of x.
Explain Show students that when different values of
x are substituted into the expression x 2 3, they get
different values for the number of marbles Simon has
more than Cynthia.
Ask If x = 5, how can you find out how many more
marbles Simon has than Cynthia? Substitute 5 for x in
the expression x − 3 to get 5 − 3 = 2. How can you
find out how many more marbles Simon has if x = 9?
Substitute 9 in the expression to get 9 − 3 = 6.
DAY 1
Algebraic expressions can be evaluated for given values of the variable.
36 advanced proofs not final pages
Lesson 2 COUrse 1 • ChapTer 7
c)
9
w4
w 20
Guided Practice
1
43x
x5
225– x
7
24
5
5
12
18
25
10 Chapter 7 AlgebraicExpressions
In e), you may want to contrast
the given expression,w4
2 4, with the expression
w 2 44
. Have students evaluate
each expression for w 5 20 to
see that the expressions are not
equivalent.
Best Practices
DIFFERENTIATED INSTRUCTION
Through Multiple Representations
You may want to point out the
efficient use of a table in Guided
Practice exercise. Some students
maybenefitfromorganizingtheir
work in Practice exercises 1 – 16
in a table.
Guided Practice 1 Remindstudentsthatan
expression such as 2x means 2 times
x. Be on the lookout for students who
forget to use the order of operations
when evaluating expressions.
b) Ask How do you evaluate x 1 12 when x 5 5?
Substitute 5 for x in the expression x 1 12. What
answer do you get? 5 1 12 5 17 What is the value
of x 1 12 when x 5 10? 22 when x 5 100? 112
c) – e) Explain Work through these examples with
students. As in b), you may want to have them evaluate
each expression for other values of the variable. Ask
students to evaluate 16 2 y, 3z 1 6, andw4
2 4 for other values of the variables.
Summarize To evaluate an expression, substitute the
given value of the variable into the expression.
Learn continued
37advanced proofs not final pages
Teacher’s editio
n
12 Chapter 7 Algebraic Expressions
Evaluate each expression for the given value of the variable.
1 x 1 x 1 5 when x 5 7 2 3x 1 5 when x 5 5
3 5y 2 8 when y 5 3 4 40 2 9y when y 5 2
5 33 2 7w 1 6 when w 5 4 6 76w when w 5 18
7 4 1 56z
when z 5 12 8 4 56
1 z when z 5 12
9 20 2 45r when r 5 10 10 8
9r 2 15 when r 5 27
11 16 2 2 43
z 2 when z 5 18 12 16 2 23z 2 4 when z 5 18
Evaluate each expression when x 5 3.
13 x 1 12
1 5 310
x 2 14 1121 x 2 9 3
4x 2
15 7 63
x 2 1 4(8 1 2x) 16 13(11 2 3x) 2 5 16 42
( )2 x
17 5(x 1 2) 1 2(6 2 x) 1 2 33
x 1 18 5 3
4x 2 1 5 5
8( )x 1 1 3(13 2 2x)
19 2 4
5x 1 2
x 1 14
1 x6
20 7x 2 x5
1 7
92 x
Evaluate each of the following when y 5 7.
21 The difference of (5y 1 2) and (2y 1 5).
22 The sum of y3
and 49y .
23 The product of ( y 1 1) and ( y 2 1).
24 The difference of 8(2y 2 1) and 14 375
y 1 .
25 The quotient of 9(7y 2 15) and 110 642 y .
26 The sum of 56y and 4
37
2y y1
.
27 The quotient of y y2
23
1
and
56 3y y
2
.
Practice 7.2
12
Basic 1 – 12
Intermediate 13 – 20
Advanced 21 – 27
19 20
7 22
11 21
14
12
1
9
0
34 29
61 16
18
48
77
13845
20
49
5
13
2
56
73
23
10
18
135
153
11Lesson 7.2 EvaluatingAlgebraicExpressions
Practice 7.2
Assignment GuideAll students should complete
1 – 20 .
21 – 28 provide additional
challenge.
Optional: Extra Practice 7.2
Write two algebraic expressions
using x that when evaluated for
x 5 3 give the same value. Show
your work. Possible answer:
3x 1 2 and 2x 1 5. When
evaluated for x 5 3,
3x 1 2 5 3(3) 1 2 5 9 1 2 5 11
2x 1 5 5 2(3) 1 5 5 6 1 5 5 11
Also available on
TeacherOneStopCD-ROM.
1
2
3
Response to Intervention Lesson Check
Before assigning homework, use the following … to make sure students … Intervene with …
Exercises 1 , 3 and 11• can evaluate simple algebraic expressions in
one variableReteach7.2
• can write and evaluate simple algebraic
expressions
In 23 , students can write the
product of ( y + 1) and ( y − 1)
before evaluating. Some students
may run into difficulties if they
try to find the product before
evaluating inside parentheses.
Best Practices
38 advanced proofs not final pages
Lesson 3 COUrse 1 • ChapTer 7
14 Chapter 7 Algebraic Expressions
p cm p cm p cm
?
p 1 p 1 p 5 3 3 p 5 3p
The perimeter of the triangle is 3p centimeters.
In the term 3p, the coefficient of p is 3.
c) The figure shows six rods and their lengths. Find the total length of the six rods in
terms of z. Then state the coefficient of the variable in the expression.
z cm z cm z cm
z cm
5 cm2 cm
z cm z cm z cm z cm 5 cm2 cm
?
z 1 z 1 z 1 z 1 2 1 5 5 (4 3 z) 1 2 1 5
5 4z 1 7
The total length of the six rods is (4z 1 7) centimeters.
In the term 4z, the coefficient of z is 4.
7 7 7
7 1 7 1 7 5 3 3 7
p p p
p 1 p 1 p 5 3 3 p
3 3 p is the same as 3p.
Add the variables
together. Then add
the numbers.
Le
arn
7.3 Simplifying Algebraic Expressions
Vocabulary
12 Chapter 7 AlgebraicExpressions
KEY CONCEPTS
• Algebraic expressions in one
variable can be simplified by
combining like terms.
• Theexpressionobtainedafter
simplifying is equivalent to the
original expression.
Simplifying Algebraic Expressions
7.3
5 5-minute Warm Up
Reviewtheconceptof
multiplication as repeated
addition. Ask students how they
can write these sums as products:
2 1 2 2 3 2 2 1 2 1 2 3 3 2
3 1 3 2 3 3 3 1 3 1 3 3 3 3
12 1 12 2 3 12
12 1 12 1 12 3 3 12
Also available on
TeacherOneStopCD-ROM.
PACING
DAY 1 Pages 12 –15
DAY 2 Pages 16 –17
DAY 3 Pages 18 – 21
Materials: paper,ruler,scissors,TR14
Learn
a) ModelUsetwobarsofthesamelengthto
represent the addition of two straws of length
yinches.Remindstudentsthatavariablerepresents
a number. Here, the variable y represents a number
that is the unknown length of a straw.
Ask What expression represents the total length of
the two straws with a length of y inches each? y 1 y
ExplainRemindstudentswhattheyhavejust
reviewed: 3 1 3 5 2 3 3, 4 1 4 5 2 3 4.
Ask Since 3 1 3 5 2 3 3 and 4 1 4 5 2 3 4, what is
y 1 y equal to? 2y If y represents any number, what
does y 1 y 5 2y mean? It means that any number
added to itself is 2 times the number.
Explain Tell students that in the term 2y, 2 is called
the coefficient of y. The term 2y means 2 times the
value of y.
Ask Given that you can represent the addition of
the same number using multiplication, how do you
show 5 1 5 1 5 using multiplication? 3 3 5
b) Ask What does perimeter mean? Sum of all sides
DAY 1
Algebraic expressions can be simplified.
39advanced proofs not final pages
Teacher’s editio
n
14 Chapter 7 Algebraic Expressions
p cm p cm p cm
?
p 1 p 1 p 5 3 3 p 5 3p
The perimeter of the triangle is 3p centimeters.
In the term 3p, the coefficient of p is 3.
c) The figure shows six rods and their lengths. Find the total length of the six rods in
terms of z. Then state the coefficient of the variable in the expression.
z cm z cm z cm
z cm
5 cm2 cm
z cm z cm z cm z cm 5 cm2 cm
?
z 1 z 1 z 1 z 1 2 1 5 5 (4 3 z) 1 2 1 5
5 4z 1 7
The total length of the six rods is (4z 1 7) centimeters.
In the term 4z, the coefficient of z is 4.
7 7 7
7 1 7 1 7 5 3 3 7
p p p
p 1 p 1 p 5 3 3 p
3 3 p is the same as 3p.
Add the variables
together. Then add
the numbers.
Le
arn
7.3 Simplifying Algebraic Expressions
Vocabulary
13Lesson 7.3 SimplifyingAlgebraicExpressions
DIFFERENTIATED INSTRUCTION
Through Visual Cues
You may want to point out the
different lengths of the rods.
Students should note that the first
four rods have the same length,
z centimeters, while the two
remaining rods have lengths of
2 centimeters and 5 centimeters
respectively.
Ask What sum represents the perimeter of the
triangle, with each side of length p centimeters?
p 1 p 1 p
ModelUsethemodeltohelpstudentstoseethat
p 1 p 1 p 5 3 3 p 5 3p.
Ask What is the coefficient of p in the term 3p? 3
c) ModelUsefourbarsofthesamelengthto
represent the addition of four rods of length
zcentimeters.Usetwootherbarsofdifferent
lengths to represent rods of length 2 centimeters
and 5 centimeters respectively.
Ask What is the sum of the variable terms? z 1 z 1 z 1
z 5 4 3 z 5 4z What is the sum of the numerical terms?
7 What is the total length of the six rods?
(4z 1 7) centimeters What is the coefficient of z in the
term 4z? 4
Summarize To simplify algebraic expressions involving
addition, first group all the variable terms together and
find their sum. Then group all the numerical terms and
find their sum.
Learn continued
40 advanced proofs not final pages
Lesson 3 COUrse 1 • ChapTer 7
16 Chapter 7 Algebraic Expressions
Work in pairs.
STEP
1 Make the following set of paper strips.
Let the length of the shortest strip be m units. Make and label 5 such strips.
RECOGNIZE THAT SIMPLIFIED EXPRESSIONS ARE EQUIVALENT
Materials:
• paper
• ruler
• scissors
m mm m m
Make and label 4 more strips of lengths 2m units, 3m units, 4m units, and 5m units.
2m 3m
4m 5m
STEP
2 Take one of the longer strips and place it horizontally.
Example
3m
STEP
3 Ask your partner to use the pieces of the shortest strips to match the length of the
chosen strip in STEP
2 .
Example
STEP
4 Write an algebraic expression to describe the number of short strips used, and
simplify it. For example in STEP
3 , write m 1 m 1 m 5 3m.
STEP
5 Repeattheactivitywithotherlengthsofstrips.
How do the lengths of the strips show that the expressions
are equivalent? In each case, the combined lengths of the short strips is equal to the length of the long strip.
5
6
4x
(3w 1 10)
x; x; x
x; x; x; 4x
3w 1 10
w; w; 10; 3w 1 10
w; w; 10
4x
Guided Practice
1 2
3 4
5x; 5 2y 1 6; 2
6n 1 4; 63m 1 9; 3
14 Chapter 7 AlgebraicExpressions
Guided Practice2 and 3 Forstudentswhohave
difficulty simplifying the expressions,
have them first draw bar models to
helpthemvisualizetheterms.
5 and 6 Askstudentstoverbalize
their work to ensure that they have
thecorrectconcept.Forexample,
w plus w plus w is equal to 3 times
w. Check in 6 that students are only
combining the like terms.
41advanced proofs not final pages
Teacher’s editio
n
16 Chapter 7 Algebraic Expressions
Work in pairs.
STEP
1 Make the following set of paper strips.
Let the length of the shortest strip be m units. Make and label 5 such strips.
RECOGNIZE THAT SIMPLIFIED EXPRESSIONS ARE EQUIVALENT
Materials:
• paper
• ruler
• scissors
m mm m m
Make and label 4 more strips of lengths 2m units, 3m units, 4m units, and 5m units.
2m 3m
4m 5m
STEP
2 Take one of the longer strips and place it horizontally.
Example
3m
STEP
3 Ask your partner to use the pieces of the shortest strips to match the length of the
chosen strip in STEP
2 .
Example
STEP
4 Write an algebraic expression to describe the number of short strips used, and
simplify it. For example in STEP
3 , write m 1 m 1 m 5 3m.
STEP
5 Repeattheactivitywithotherlengthsofstrips.
How do the lengths of the strips show that the expressions
are equivalent? In each case, the combined lengths of the short strips is equal to the length of the long strip.
5
6
4x
(3w 1 10)
x; x; x
x; x; x; 4x
3w 1 10
w; w; 10; 3w 1 10
w; w; 10
4x
Guided Practice
1 2
3 4
5x; 5 2y 1 6; 2
6n 1 4; 63m 1 9; 3
15Lesson 7.3 SimplifyingAlgebraicExpressions
Hands-On ActivityThis activity reinforces the concept
of simplifying algebraic expressions
through a concrete approach. Have
students work in pairs.
Optional Materials:TR14,Paper
Strips
1 Make sure students cut the
same length for all the 5 strips
of length m units. When making
the strips for lengths of 2m units,
3m units, 4m units, and 5m units,
tell students that the length of
2m must be 2 times the length
of m, the length of 3m must be
3 times the length of m, and
so on.
4 Make sure students understand
that writing the algebraic
expression represents the action
carried out in 3 .
Guide
students to see that by
matching the number of
individual strips against a single
strip of the same length, they are
demonstrating that an addition
expression and the simplified form
of the expression are equivalent.
Forexample,thesumm 1 m 1 m is
equal to the product of 3 and m.
42 advanced proofs not final pages
Lesson 3 COUrse 1 • ChapTer 7
18 Chapter 7 Algebraic Expressions
Le
arn Like terms can be subtracted.
a) Simplify 2v 2 v.
2v
v v
2v 2 v 5 v
b) Simplify 5w 2 3w.
5w
3w
w ww w w
5w 2 3w 5 2w
c) Simplify y 2 y.
y 2 y 5 0
2v 2 v and v are equivalent
expressions because they are
equal for all values of v.
If v 5 2, 2v 2 v 5 2 and v 5 2.
If v 5 3, 2v 2 v 5 3 and v 5 3.
Math Note
Any term that is subtracted from
itself is equal to zero.
Guided PracticeComplete.
16 Simplify 4s 2 s.
s ss s
?
?
4s 2 s 5 ?
Simplify each expression.
17 12z 2 7z 18 3p 2 3p
State whether each pair of expressions are equivalent.
19 f 2 6 and 6 2 f 20 5c 2 5c and a 2 a EquivalentNot equivalent
4s
3s
5z 0
s
Le
arn
Guided Practice
7
8 9
10 11
12 13
14 15
9x
5r
Equivalent
Not equivalent Not equivalent
EquivalentNot equivalent
Equivalent
11y
x 8x
16 Chapter 7 AlgebraicExpressions
Students may not understand that
the variable x has a coefficient of
1.Emphasizethat,whenusing
a bar model for the expression,
you use one bar for the x term, to
show one group of x.
Best Practices
Guided PracticeUse 7 to reinforce the idea that
the coefficient of x is 1, so that
x 1 8x 5 9x.
8 and 9 Remindstudentsthatthe
coefficient of a term tells you how
manygroupsarebeingadded.For
example, 3r 1 2r means 3 groups
of r plus 2 groups of r.
Learn
a) ModelUsefourbarsofthesamelengthtomodel
3x 1 x.
ExplainExplainthatsince3x 5 x 1 x 1 x, the
expression 3x 1 x means x 1 x 1 x 1 x, or 4x.
Students should interpret 3x 1 x as 3 groups of x
plus 1 group of x, giving a total of 4 groups of x,
or 4x.
Explain Tell students that 3x and x are called like
terms.Emphasizethatonlyliketermscanbeadded.
Ask What are some other examples of like terms?
Possible answers: 5m and 7m, 4 and 6
Explain Point out that when two expressions
are equal for all values of the variables, they are
equivalent expressions. Since 3x 1 x 5 4x for all
values of x, 3x 1 x and 4x are equivalent expressions.
b) Model Model 4z 1 2z as in a).
Ask When you add 4 groups of z to 2 groups of
z, how many groups of z do you have? 6 What
expression represents 6 groups of z? 6z
Ask What are the equivalent expressions in the
example 4z 1 2z 5 6z? 4z 1 2z and 6z
DAY 2
Like terms can be added.
43advanced proofs not final pages
Teacher’s editio
n
18 Chapter 7 Algebraic Expressions
Le
arn Like terms can be subtracted.
a) Simplify 2v 2 v.
2v
v v
2v 2 v 5 v
b) Simplify 5w 2 3w.
5w
3w
w ww w w
5w 2 3w 5 2w
c) Simplify y 2 y.
y 2 y 5 0
2v 2 v and v are equivalent
expressions because they are
equal for all values of v.
If v 5 2, 2v 2 v 5 2 and v 5 2.
If v 5 3, 2v 2 v 5 3 and v 5 3.
Math Note
Any term that is subtracted from
itself is equal to zero.
Guided PracticeComplete.
16 Simplify 4s 2 s.
s ss s
?
?
4s 2 s 5 ?
Simplify each expression.
17 12z 2 7z 18 3p 2 3p
State whether each pair of expressions are equivalent.
19 f 2 6 and 6 2 f 20 5c 2 5c and a 2 a EquivalentNot equivalent
4s
3s
5z 0
s
Le
arn
Guided Practice
7
8 9
10 11
12 13
14 15
9x
5r
Equivalent
Not equivalent Not equivalent
EquivalentNot equivalent
Equivalent
11y
x 8x
17Lesson 7.3 SimplifyingAlgebraicExpressions
Guided PracticeLook out for students who claim
that the expressions in 20 are not
equivalent. They may be thinking that
the word “equivalent” applies only to
an expression and the simplified form
ofthatexpression.Remindthemthat
“equivalent” means having the same value.
Learn
Like terms can be subtracted.
a) Ask What does 2v 2 v mean? 2 groups of v minus
1 group of v
Model Usetwobarsofthesamelengthto
represent 2v. Show that one bar is to be removed
from the diagram. Lead students to see that
2v 2 v 5 v.
b) Model Have students interpret the model 5w 2 3w.
Ask How many groups of w do you start with? 5
How many groups do you subtract? 3From
the model, how many groups of w are left after
subtraction? 2
c) Ask If a ribbon of length y centimeters is used up to
tie a gift, what is the length of the ribbon left?
0 centimeters
Explain Reinforcebyshowingexamplessuchas
2 2 2 5 0, and 15 2 15 5 0. Therefore, y 2 y 5 0.
Ask When you subtract a number from itself, what
answer do you get? 0
Summarize Any term that is subtracted from itself is
equaltozero.
44 advanced proofs not final pages
Lesson 3 COUrse 1 • ChapTer 7
20 Chapter 7 Algebraic Expressions
b) Simplify 5x 2 2 1 3x.
5x 2 2 1 3x Identify like terms.
5 5x 1 3x 2 2 Change the order of terms
to collect like terms.
5 8x 2 2 Simplify.
Caution8x 2 2 6x because 8x and 2 are
not like terms. 8x 2 2 cannot be
simplified further.
5x 2 2 1 3x and 8x 2 2 are equivalent
expressions because they are equal for all
values of x.
If x 5 2, 5x 2 2 1 3x 5 14 and 8x 2 2 5 14.
If x 5 3, 5x 2 2 1 3x 5 22 and 8x 2 2 5 22.
Guided PracticeComplete.
27 The figure shows a quadrilateral. Find the perimeter of the quadrilateral.
6x 1 6 1 2x 1 2 5 6x 1 2x 1 6 1 2
5 ? 1 ?
The perimeter of the quadrilateral is ? units.
Simplify each expression.
28 4x 2 3 1 3x 29 5y 1 4 2 2y
30 8y 2 7 2 4y 31 7z 1 9 2 2z 2 2
32 5 1 11z 2 4 1 6z 33 8g 1 10 2 3g 1 7
34 12 1 6g 2 5 2 4g 35 27 1 3r 2 9 1 15r
2x units
6x units
2 units6 units
8x; 8
7x 2 3
4y 2 7
17z 11
2g 17
8x 18
5g 117
3y 14
5z 17
18r 118
Le
arn
Le
arn
Work from left to right.
Add.
Work from left to right.
Subtract.
c)
Work from left to right.
Add.
Guided Practice
21 22
23 24
25 26
Caution
Identify like terms.
Change the order of terms
to collect like terms.
Simplify.
Math Note
4j 11j
3w
0
6j
2t
5w
18 Chapter 7 AlgebraicExpressions
Guided PracticeWatch out for students who forget
to work from left to right in 23 to 26 .
Remindthemtofollowtheorderof
operations.
DAY 3
Learn
a) Explain Compare simplifying a numerical expression to simplifying an
algebraic one.
Ask How do you evaluate this expression 1 + 6 + 2? Work from left to
right: 1 + 6 + 2 = 7 + 2 = 9. Given the expression x + 6x + 2x, what is
your first step in simplifying it? Simplify x + 6x to get 7x. What is the next
step? Simplify 7x + 2x to get 9x.
Explain Make sure students see how the expressions in parts b and c
are different from the one in part a. In each case, the process for
simplifying is to work from left to right.
Summarize When adding and subtracting algebraic terms without
parentheses, always work from left to right.
Use order of operations to simplify algebraic expressions.
Learn
a) Ask Since the perimeter of
the parallelogram is r 1 8 1
r 1 8, how can you simplify
the expression? Reorderand
combine the like terms:
r 1 r 1 8 1 8 5 2r 1 16.
Can 2r 1 16 be simplified
further? No Why? 2r and 16
are not like terms.
Collect like terms to simplify algebraic expressions.
To reinforce understanding,
you may want to have students
analyzemathematicalstatements
in the Caution. Make sure they
understand that in each of the
“wrong” examples, the addition
and subtraction have not been
performed from left to right,
which leads to an incorrect result.
Best Practices
45advanced proofs not final pages
Teacher’s editio
n
20 Chapter 7 Algebraic Expressions
b) Simplify 5x 2 2 1 3x.
5x 2 2 1 3x Identify like terms.
5 5x 1 3x 2 2 Change the order of terms
to collect like terms.
5 8x 2 2 Simplify.
Caution8x 2 2 6x because 8x and 2 are
not like terms. 8x 2 2 cannot be
simplified further.
5x 2 2 1 3x and 8x 2 2 are equivalent
expressions because they are equal for all
values of x.
If x 5 2, 5x 2 2 1 3x 5 14 and 8x 2 2 5 14.
If x 5 3, 5x 2 2 1 3x 5 22 and 8x 2 2 5 22.
Guided PracticeComplete.
27 The figure shows a quadrilateral. Find the perimeter of the quadrilateral.
6x 1 6 1 2x 1 2 5 6x 1 2x 1 6 1 2
5 ? 1 ?
The perimeter of the quadrilateral is ? units.
Simplify each expression.
28 4x 2 3 1 3x 29 5y 1 4 2 2y
30 8y 2 7 2 4y 31 7z 1 9 2 2z 2 2
32 5 1 11z 2 4 1 6z 33 8g 1 10 2 3g 1 7
34 12 1 6g 2 5 2 4g 35 27 1 3r 2 9 1 15r
2x units
6x units
2 units6 units
8x; 8
7x 2 3
4y 2 7
17z 11
2g 17
8x 18
5g 117
3y 14
5z 17
18r 118
Le
arn
Le
arn
Work from left to right.
Add.
Work from left to right.
Subtract.
c)
Work from left to right.
Add.
Guided Practice
21 22
23 24
25 26
Caution
Identify like terms.
Change the order of terms
to collect like terms.
Simplify.
Math Note
4j 11j
3w
0
6j
2t
5w
19Lesson 7.3 SimplifyingAlgebraicExpressions
Guided Practice27 to 34 and 36 Check that students
have two terms in each of their final
expressions. Students who end up
with one term do not understand that
unlike terms cannot be combined.
b) Explain Make sure students understand that they
must change the order of the terms so that they can
add 5x and 3x to get 8x, and that 2 is subtracted
from the result.
Ask What are the like terms in 5x 2 2 1 3x? 5x and
3x If you want to add the like terms, how can you
rewrite the expression? 5x 1 3x 2 2 5 8x 2 2
Explain Emphasizethat8x 2 2 cannot be simplified
further because 8x and 2 are not like terms.
Learn continued
As students develop ideas
about combining like terms,
make sure they understand that
the operation symbol in front
of a term determines how it is
combined with other like terms.
Forexample,inb), students
should see that 2 is being
subtracted. When the terms
are reordered, 2 must still be
subtracted from 5.
Best Practices
46 advanced proofs not final pages
Lesson 3 COUrse 1 • ChapTer 7
1
2
3
4 5 6
7 8
9 10
11 12
13 123v
15 16
17 18
19
20
Practice 7.3 Basic 1 – Intermediate 21 – 23 , 26
Advanced 24 –
Not equivalent
Not equivalent
Not equivalent
Equivalent
4u; 4
4p 9p 5p
p6p
2v 1 3; 2
6w 1 8; 6
7x 1 11 8x 1 2
3w 1 5 3u 1 6
(4b 1 4) inches
(3z 1 15) cm
Equivalent
Equivalent
22 Chapter 7 Algebraic Expressions
21 Anne is currently h years old. Bill is currently 2h years old and Charles is
currently 8 years old. Find an expression for each person’s age after h years.
Then find an expression for the sum of their ages after h years.
22 There are 18 boys in a class. There are w fewer boys than girls. How many
students are there in the class?
23 A rectangular garden has a length of ( y 1 2) yards and a width of (4y 2 1) yards.
Find the perimeter of the garden in terms of y.
24 Kayla had 64b dollars. She gave 18
of it to Luke and spent $45. How much
money did Kayla have left? Express your answer in terms of b.
25 A rectangle has a length of (2m 1 1) units and a width of (10 2 m ) units.
A square has sides of length 2 1
2m 1
units.
a) Find the perimeter of the rectangle.
b) Find the perimeter of the square.
c) Find the sum of the perimeters of the two figures if m 5 6.
d) Find the difference between the perimeter of the rectangle and the
perimeter of the square if m 5 6.
26 Ritasimplifiedtheexpression10w 2 5w 1 2w in this way:
10w – 5w + 2w = 10w – 7w = 3w
IsRita’sanswercorrect?Ifnot,explainwhyitisincorrect.
(w 1 36) students
(10y 1 2) yards
(2m 1 22) units
(4m 1 2) units
60 units
8 units
No,itisnotcorrect.Ritadidnot work from left to right when simplifying the expression.
(56b 2 45) dollars
Anne: 2h; Bill: 3h; Charles: 8 1 h; Sum: 6h 1 8
Practice 7.3
20 Chapter 7 AlgebraicExpressions
Assignment Guide
DAY 1 All students should
complete 1 – 3 .
DAY 2 All students should
complete 4 – 6 .
DAY 3 All students should
complete 7 – 23 , 26 .
24 – 25 provide additional
challenge.
Optional: Extra Practice 7.3
1
2
3
Response to Intervention Lesson Check
Before assigning homework, use the following … to make sure students … Intervene with …
Exercises 1 , 3 and 8
• can simplify simple algebraic expressions
involving addition and subtraction of like
terms
Reteach7.3Exercises 9 and 14
• check whether two algebraic expressions are
equivalent
• write an algebraic expression to represent a
situation and simplify that expression
Practice 7.3
47advanced proofs not final pages
Teacher’s editio
n
1
2
3
4 5 6
7 8
9 10
11 12
13 123v
15 16
17 18
19
20
Practice 7.3 Basic 1 – Intermediate 21 – 23 , 26
Advanced 24 –
Not equivalent
Not equivalent
Not equivalent
Equivalent
4u; 4
4p 9p 5p
p6p
2v 1 3; 2
6w 1 8; 6
7x 1 11 8x 1 2
3w 1 5 3u 1 6
(4b 1 4) inches
(3z 1 15) cm
Equivalent
Equivalent
22 Chapter 7 Algebraic Expressions
21 Anne is currently h years old. Bill is currently 2h years old and Charles is
currently 8 years old. Find an expression for each person’s age after h years.
Then find an expression for the sum of their ages after h years.
22 There are 18 boys in a class. There are w fewer boys than girls. How many
students are there in the class?
23 A rectangular garden has a length of ( y 1 2) yards and a width of (4y 2 1) yards.
Find the perimeter of the garden in terms of y.
24 Kayla had 64b dollars. She gave 18
of it to Luke and spent $45. How much
money did Kayla have left? Express your answer in terms of b.
25 A rectangle has a length of (2m 1 1) units and a width of (10 2 m ) units.
A square has sides of length 2 1
2m 1
units.
a) Find the perimeter of the rectangle.
b) Find the perimeter of the square.
c) Find the sum of the perimeters of the two figures if m 5 6.
d) Find the difference between the perimeter of the rectangle and the
perimeter of the square if m 5 6.
26 Ritasimplifiedtheexpression10w 2 5w 1 2w in this way:
10w – 5w + 2w = 10w – 7w = 3w
IsRita’sanswercorrect?Ifnot,explainwhyitisincorrect.
(w 1 36) students
(10y 1 2) yards
(2m 1 22) units
(4m 1 2) units
60 units
8 units
No,itisnotcorrect.Ritadidnot work from left to right when simplifying the expression.
(56b 2 45) dollars
Anne: 2h; Bill: 3h; Charles: 8 1 h; Sum: 6h 1 8
21Lesson 7.3 SimplifyingAlgebraicExpressions
Write an algebraic expression for
the perimeter of a rectangular
garden with a width of 3 feet and
a length of 2y feet. Simplify your
expression and find the perimeter
of the garden if y 5 6. Show your
work. 3 1 2y 1 3 1 2y; 6 1 4y;
30 ft
Also available on
TeacherOneStopCD-ROM.
You may want to suggest students
use a bar model for 22 .Usinga
model may help them see that the
total number of girls is 18 + w.
Best Practices
48 advanced proofs not final pages
Lesson 4 COUrse 1 • ChapTer 7
24 Chapter 7 Algebraic Expressions
3(k 1 6) and 3k 1 18 are equivalent
expressions because they are equal for
all values of k.
3 3 (k 1 6)
5 (k 1 6) 1 (k 1 6) 1 (k 1 6)
5 k 1 k 1 k 1 6 1 6 1 6
5 3k 1 18
Guided PracticeExpand each expression.
1 3(x 1 4) 2 6(2x 1 3) 3 2(7 1 6x)
4 5( y 2 3) 5 4(4y 2 1) 6 9(5x 2 2)
State whether each pair of expressions are equivalent.
7 6(x 1 5) and 6x 1 30 8 7(x 1 3) and 21 1 7x
9 4( y 2 4) and 4y 2 4 10 3( y 2 6) and 18 2 3y
b) Expand 3(k 1 6).
3(k 1 6) means 3 groups of k 1 6:
1 group
k k k6 6 6
Rearrangethetermstocollecttheliketerms:
3 3 k 3 3 6
k k k 6 6 6
From the models,
3(k 1 6) 5 3 3 (k 1 6)
5 3 3 k 1 3 3 6
5 3k 1 18
3k 1 18 is the expanded form of 3(k 1 6).
Equivalent
Not equivalentNot equivalent
Equivalent
3x 1 12 12x 1 18 14 1 12x
5y 2 15 16y 2 4 45x 2 18
Le
arn
7.4 Expanding and Factoring Algebraic Expressions
2
2
Vocabulary
22 Chapter 7 AlgebraicExpressions
5
KEY CONCEPT
• Expandingistheoppositeprocess
of factoring.
Expanding and Factoring Algebraic Expressions
7.4
5-minute Warm Up
Reviewwithstudentsthe
distributive property of
multiplication over addition and
subtraction.
6 3 (5 1 2) 5 6 3 5 1 6 3 2
4 3 (7 2 3) 5 4 3 7 2 4 3 3
Also available on
TeacherOneStopCD-ROM.
PACING
DAY 1 Pages 22–24
DAY 2 Pages 25–28
Materials: paper, ruler, scissors,
yardsticks
Learn
a) Ask What does 2(r 1 8) mean? 2 groups of (r 1 8)
ModelUseabarmodeltoshow2groupsof
(r 1 8). Then rearrange the model such that the two
bars of “r” are put together and the two bars
of “8” are put together.
Explain Tell students that the two bars of “r”
represent 2 3 r and the two bars of “8” represent
2 3 8.
Model Show students how 2(r 1 8) is expanded
using the distributive property. Mention that 2r 1 16
is the expanded form of 2(r 1 8).
Explain Get students to deduce from the
model that 2(r 1 8) 5 2 3 r 1 2 3 8 5 2r 1 16.
Alternatively, lead students to see that
2 3 (r 1 8) 5 (r 1 8) 1 (r 1 8) 5 r 1 r 1 8 1 8
5 2r 1 16.
Ask Since 2(r 1 8) 5 2r 1 16, what do you call
the expressions 2(r 1 8) and 2r 116? Equivalent
expressions How do you check if the expressions
are equivalent? Substitute any value of r into the
expressions and check if they are equal.
DAY 1
Use the distributive property to expand algebraic expressions.
49advanced proofs not final pages
Teacher’s editio
n
24 Chapter 7 Algebraic Expressions
3(k 1 6) and 3k 1 18 are equivalent
expressions because they are equal for
all values of k.
3 3 (k 1 6)
5 (k 1 6) 1 (k 1 6) 1 (k 1 6)
5 k 1 k 1 k 1 6 1 6 1 6
5 3k 1 18
Guided PracticeExpand each expression.
1 3(x 1 4) 2 6(2x 1 3) 3 2(7 1 6x)
4 5( y 2 3) 5 4(4y 2 1) 6 9(5x 2 2)
State whether each pair of expressions are equivalent.
7 6(x 1 5) and 6x 1 30 8 7(x 1 3) and 21 1 7x
9 4( y 2 4) and 4y 2 4 10 3( y 2 6) and 18 2 3y
b) Expand 3(k 1 6).
3(k 1 6) means 3 groups of k 1 6:
1 group
k k k6 6 6
Rearrangethetermstocollecttheliketerms:
3 3 k 3 3 6
k k k 6 6 6
From the models,
3(k 1 6) 5 3 3 (k 1 6)
5 3 3 k 1 3 3 6
5 3k 1 18
3k 1 18 is the expanded form of 3(k 1 6).
Equivalent
Not equivalentNot equivalent
Equivalent
3x 1 12 12x 1 18 14 1 12x
5y 2 15 16y 2 4 45x 2 18
Le
arn
7.4 Expanding and Factoring Algebraic Expressions
2
2
Vocabulary
23Lesson 7.4 ExpandingandFactoringAlgebraicExpressions
ELL Vocabulary Highlight
Make sure that students
understand that equivalent
expressions evaluated for the
same value of the variable are
equal.Forexample,forx 5 3,
2x 2 4 5 2
2(x 2 2) 5 2
Guided PracticeTell students it is best to use the
distributive property to expand
algebraic expressions.
4 to 6 Remindstudentstowatch
the signs in the parentheses when
expanding expressions.
7 to 10 Remindstudentstoonly
combine like terms after expanding.
Be sure that students understand
that variable terms with a
coefficient such as 6x are
expanded the same way as
variables without a coefficient.
They are multiplied by the factor
outsidetheparentheses.For
example, in 3 , the 6x becomes
2 3 6x or 12x.
Best Practices
b) Model Have students interpret the model 3(k 1 6).
Then rearrange the bars such that the three bars of
“k” are put together and the three bars of “6” are
put together.
Explain Tell students that the three bars of “k”
represent 3 3 k and the three bars of “6” represent
3 3 6.
Ask How do you expand 3(k 1 6)? 3(k 1 6) 5
3 3 k 1 3 3 6 5 3k 1 18 What do you call the
expressions 3(k 1 6) and 3k 1 18? Equivalent
expressions How do you check if the expressions
are equivalent? Substitute any value of k into the
expressions and check if they are equal.
Learn continued
50 advanced proofs not final pages
STEP
1
STEP
2
STEP
3
STEP
4
STEP
5STEP
2STEP
4
STEP
6
RECOGNIZE THAT EXPANDED EXPRESSIONS ARE EQUIVALENT
Materials:
(8p 1 24) cm2
8p cm2, 24 cm2
Area of big rectangle 5 Area of rectangle A 1 Area of rectangle B
26 Chapter 7 Algebraic Expressions
Le
arn
To factor an
expression, look
for common factors
in the terms of the
expression.
Since they are equal for all values of y, 2y 1 10
and 2( y 1 5) are equivalent expressions.
Factoring is the inverse
of expanding. You can
use expanding to check
if you have factored an
expression correctly.
Algebraic expressions can be factored by taking out a common factor.
You can expand the expression 3(4z 1 1) by writing it as 12z 1 3.
You can also start with the expression 12z 1 3 and write it as 3(4z 1 1).
When you write 12z 1 3 as 3(4z 1 1), you have factored 12z 1 3.
a) Factor 2y 1 10.
List the factors of each term in the expression.
10 5 1 3 10 2y 5 1 3 2y 5 2 3 5 5 2 3 y
The factors of 10 are 1, 2, 5, and 10.
The factors of 2y are 1, 2, y, and 2y.
Excluding 1, the common factor of 10 and 2y is 2.
2y 1 10 5 2 3 y 1 2 3 5 5 2 3 ( y 1 5) Take out the common factor 2.
5 2( y 1 5)
2( y 1 5) is the factored form of 2y 1 10.
Check: Expand the expression 2( y 1 5) to
check the factoring.
2( y 1 5) 5 2 3 y 1 2 3 5
5 2y 1 10
2y 1 10 is factored correctly.
Continue on next page
24 Chapter 7 AlgebraicExpressions
Hands-On ActivityThis activity shows a concrete
representation of the distributive
property used for expanding
algebraic expressions such as
8(p 1 3). By equating the area of
the large rectangle to the sum
of the areas of the two smaller
rectangles, students can see the
concrete representation of
8(p 1 3) 5 8p 1 24.
2 Guide students to find the area
of the rectangle by reminding
them about the formula for area
of a rectangle, length 3 width.
Make sure students remember
how to expand the expression.
5 Make sure students see that the
sum of the area of rectangle A
and the area of rectangle B is
equal to the area of the original
rectangle.
Lesson 4 COUrse 1 • ChapTer 7
51advanced proofs not final pages
Teacher’s editio
nSTEP
1
STEP
2
STEP
3
STEP
4
STEP
5STEP
2STEP
4
STEP
6
RECOGNIZE THAT EXPANDED EXPRESSIONS ARE EQUIVALENT
Materials:
(8p 1 24) cm2
8p cm2, 24 cm2
Area of big rectangle 5 Area of rectangle A 1 Area of rectangle B
26 Chapter 7 Algebraic Expressions
Le
arn
To factor an
expression, look
for common factors
in the terms of the
expression.
Since they are equal for all values of y, 2y 1 10
and 2( y 1 5) are equivalent expressions.
Factoring is the inverse
of expanding. You can
use expanding to check
if you have factored an
expression correctly.
Algebraic expressions can be factored by taking out a common factor.
You can expand the expression 3(4z 1 1) by writing it as 12z 1 3.
You can also start with the expression 12z 1 3 and write it as 3(4z 1 1).
When you write 12z 1 3 as 3(4z 1 1), you have factored 12z 1 3.
a) Factor 2y 1 10.
List the factors of each term in the expression.
10 5 1 3 10 2y 5 1 3 2y 5 2 3 5 5 2 3 y
The factors of 10 are 1, 2, 5, and 10.
The factors of 2y are 1, 2, y, and 2y.
Excluding 1, the common factor of 10 and 2y is 2.
2y 1 10 5 2 3 y 1 2 3 5 5 2 3 ( y 1 5) Take out the common factor 2.
5 2( y 1 5)
2( y 1 5) is the factored form of 2y 1 10.
Check: Expand the expression 2( y 1 5) to
check the factoring.
2( y 1 5) 5 2 3 y 1 2 3 5
5 2y 1 10
2y 1 10 is factored correctly.
Continue on next page
25Lesson 7.4 ExpandingandFactoringAlgebraicExpressions
CautionStudents may not understand
that the phrase “Take out” means
moving the common factor and
placing the y 1 5 in parentheses.
In a), the common factor is 2.
Doingthisistheoppositeof
applying the distributive property.
Learn
AskExpand3(4z 1 1). What do you get? 12z 1 3
Explain 12z 1 3 is the expanded form of 3(4z 1 1).
Since 12z 1 3 and 3(4z 1 1) are equivalent expressions,
12z 1 3 5 3(4z 1 1). Tell students that they have
factored 12z 1 3. Make sure students see how factoring
and expanding are related.
a) Explain To factor 2y 1 10, find the common
factor(s) of 2y and 10. In order to find the common
factor(s) of the two terms, you list the factors of
each term. Point out to students that 1 is excluded
because 1 is a factor of every term. Write 2y 1 10
5 2 3 y 1 2 35ontheboard.Next,takeoutthe
common factor and write 2( 1 ).
Ask What terms should you write in the blank
spaces? y and 5 How can you check your answer? By
expanding 2( y 1 5) Since 2y 1 10 5 2( y 1 5), what
do you call the expressions 2y 1 10 and 2( y 1 5)?
Equivalentexpressions
Explain Tell students that factoring is the opposite
process of expanding. You can use expanding to
check if you have factored an expression correctly.
Algebraic expressions can be factored by taking a common factor.
DAY 2
52 advanced proofs not final pages
3
3 Take out the common factor 3.
Guided Practice
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26Equivalent
Equivalent
3(x 1 1)
5( y 2 2)
2(2 2 5z) 4(3 2 2x)
5(3 1 q)
4(3t 2 2)2(4f 1 3)
2(2x 1 3)
8(4m 2 5)
2(4 1 3y)
Equivalent
Not equivalent Not equivalent
Not equivalent
26 Chapter 7 AlgebraicExpressions
Guided Practice16 , 18 and 20 Remindstudentsthat
in factoring, they should look for the
greatest common factor of the terms
in the expression.
b) Ask Whatarethetermsintheexpression6z2 9?
6zand9
Explain To factor 6z 2 9, find the common factor(s)
of 6zand9.Remindstudentsthat1isexcluded
because 1 is a factor of every term.
Ask What are the factors of 6z and 9? 6: 3 and 2;
9: 3 What is the common factor of 6z and 9? 3
Explain Write 6z 2 9 5 3 3 2z 2 3 3 3 on the
board.Next,takeoutthecommonfactorandwrite
3( 2 ).
Ask What terms should you write in the blank spaces?
2z and 3 How can you check your answer? By expanding
3(2z 2 3) Since 6z 2 9 5 3(2z 2 3), what do you call
the expressions 6z 2 9 and 3(2z 2 3)? Equivalent
expressions
Explain Tell students that 3(2z 2 3) is the factored form
of 6z 2 9.
Learn continued
Lesson 4 COUrse 1 • ChapTer 7
53advanced proofs not final pages
Teacher’s editio
n
28 Chapter 7 Algebraic Expressions
Expand each expression.
1 5(x 1 2) 2 7(2x 2 3)
3 4( y 2 3) 4 8(3y 2 4)
5 3(x 1 11) 6 9(4x 2 7)
Factor each expression.
7 6p 1 6 8 3p 1 18
9 12 1 3q 10 4w 2 16
11 14r 2 8 12 12r 2 12
State whether each pair of expressions are equivalent.
13 4x 1 12 and 4(x 1 3) 14 5(x 2 1) and 5x 2 1
15 7(5 1 y) and 7y 1 35 16 9( y 2 2) and 18 2 9y
Expand each expression.
17 3(m 1 2) 1 4(6 1 m)
18 5(2p 1 5) 1 4(2p 2 3)
19 4(6k 1 7) 1 9 2 14k
Simplify each expression. Then factor the expression.
20 14x 1 13 2 8x 2 1
21 8( y 1 3) 1 6 2 3y
22 4( 3z 1 7) 1 5(8 1 6z)
Solve.
23 Expand and simplify the expression 3(x 2 2) 1 9(x 1 1) 1 5(1 1 2x) 1 2(3x 2 4).
Practice 7.4
Not equivalentEquivalent
Not equivalentEquivalent
2(21z 1 34)
5( y 1 6)
6( x 1 2)
10k 1 37
18p 1 13
7m 1 30
12(r 2 1)
4(w 2 4)
3(p 1 6)6(p 1 1)
5x 1 10 14x 2 21
4y 2 12 24y 2 32
36x 2 633x 1 33
3(4 1 q)
2(7r 2 4)
28x
Basic 1 – 16
Intermediate 17 – 22
Advanced 23 – 27
27Lesson 7.4 ExpandingandFactoringAlgebraicExpressions
Practice 7.4
Assignment Guide
DAY 1 All students should
complete 1 – 6
and 17 – 19 .
DAY 2 All students should
complete 7 – 16 .
and 20 – 22 .
23 – 27 provide additional
challenge.
Optional: Extra Practice 7.4
You may want to highlight the
grouping symbols: parentheses.
Have students work with the
parentheses first. So for 18 ,
students would first expand
5(2p 1 5) to 10p 1 25 and
4(2p 2 3) to 8p 2 12. Then,
they would collect like terms,
10p 1 8p 1 25 2 12 5 18p 1 13.
Best Practices
1
2
3
Response to Intervention Lesson Check
Before assigning homework, use the following … to make sure students … Intervene with …
Exercises 1 , 3 and 6 • can expand simple algebraic expressions
Reteach7.4Exercises 9 and 12 • can factor simple algebraic expressions
• can write, expand, and evaluate simple
algebraic expressions
54 advanced proofs not final pages
24
25
26
27
BC
a)
Equivalent
(3w 1 80) cents
(10m 1 9) pounds
(x 1 2) cm; (3x 1 6) cm2
Unshadedrectangle5 3x cm2, shaded rectangle 5 6 cm2
Sum of area of smaller rectangles 5 Area of rectangle ABCD 3x 1 6 5 3(x 1 2)Thus, the expressions 3x 1 6 and 3(x 1 2) are equivalent.
30 Chapter 7 Algebraic Expressions
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7.5 Real-World Problems: Algebraic Expressions
Lesson Objective• Solvereal-worldproblemsinvolvingalgebraicexpressions.
Write an addition or subtraction algebraic expression for a real-world problem and evaluate it.
The figure shows a triangle ABC.
a) What is the perimeter of the triangle ABC in terms of s?
?
s cm s cm 10 cm
s 1 s 1 10 5 2s 1 10
The perimeter of the triangle ABC is (2s 1 10) centimeters.
b) The perimeter of a trapezoid is 7 cm shorter than the perimeter of triangle ABC.
Find the perimeter of the trapezoid.
(2s 1 10) cm
? 7 cm
2s 1 10 2 7 5 2s 1 3
The perimeter of the trapezoid is (2s 1 3) centimeters.
c) If s 5 7, find the perimeter of the triangle ABC.
When s 5 7,
2s 1 10 5 (2 3 7) 1 10
5 14 1 10
5 24
The perimeter of the triangle ABC is 24 centimeters.
AC 5 s cm. Since
AC 5 7 cm, s 5 7.
s cm s cm
10 cm
A
B C
28 Chapter 7 AlgebraicExpressions
DIFFERENTIATED INSTRUCTION
Through Visual Cues
For25 , use three yardsticks, one
to represent a yard of lace, and
the other two to represent
2 yards of fabric. Ask students to
write an expression for the cost of
the lace, w, and 2 yards of fabric
2(w 1 40). Have students find the
total cost of the lace and fabric,
w 1 2w 1 80 5 (3w 1 80) cents.
Write an algebraic expression
and expand it by multiplying by a
factor.Evaluatebothexpressions
for the same value of the variable.
Check that the answers to the
evaluations are the same. Possible
answer:
4z 2 5, 3(4z 2 5) 5 12z 2 15;
Let z 5 2.
3(4z 2 5) 5 3(4 3 2 2 5)
5 3(8 2 5)
5 3(3) 5 9 3
12z 2 15 5 12 3 2 2 15
5 24 2 15 5 9 3
Also available on
TeacherOneStopCD-ROM.
Lessons 4 and 5 COUrse 1 • ChapTer 7
55advanced proofs not final pages
Teacher’s editio
n
30 Chapter 7 Algebraic Expressions
Le
arn
7.5 Real-World Problems: Algebraic Expressions
Lesson Objective• Solvereal-worldproblemsinvolvingalgebraicexpressions.
Write an addition or subtraction algebraic expression for a real-world problem and evaluate it.
The figure shows a triangle ABC.
a) What is the perimeter of the triangle ABC in terms of s?
?
s cm s cm 10 cm
s 1 s 1 10 5 2s 1 10
The perimeter of the triangle ABC is (2s 1 10) centimeters.
b) The perimeter of a trapezoid is 7 cm shorter than the perimeter of triangle ABC.
Find the perimeter of the trapezoid.
(2s 1 10) cm
? 7 cm
2s 1 10 2 7 5 2s 1 3
The perimeter of the trapezoid is (2s 1 3) centimeters.
c) If s 5 7, find the perimeter of the triangle ABC.
When s 5 7,
2s 1 10 5 (2 3 7) 1 10
5 14 1 10
5 24
The perimeter of the triangle ABC is 24 centimeters.
AC 5 s cm. Since
AC 5 7 cm, s 5 7.
s cm s cm
10 cm
A
B C
29Lesson 7.5 Real-WorldProblems:AlgebraicExpressions
5
KEY CONCEPT
• The process of problem solving
involves the application of
concepts, skills and strategies.
Real-World Problems: Algebraic Expressions
7.5
5-minute Warm Up
Demonstratehowtosolvethis
problem:
Jim has x stamps. His friend gives
him 20 stamps and he gives 15 in
return. How many stamps does
Jim have now?
x 1 20 215 5 x 1 5
Also available on
TeacherOneStopCD-ROM.
PACING
DAY 1 Pages 29–32
DAY 2 Pages 32–35
Materials: none
Learn
a) Model Work through a) with students to
demonstrate the problem solving process.
Step 1Understandtheproblem.
Ask What is given in the problem? The lengths of
the sides of the triangle What are you asked to find?
The perimeter of the triangle
Step 2 Decideonastrategytouse.
Ask How can you find the perimeter of the triangle?
Add the side lengths. Are the lengths of the triangle
given? Yes What are they? s cm, s cm, and 10 cm
Step 3 Solve the problem.
Ask What expression do you get? s 1 s 1 10 Can the
expression be simplified? Yes, s 1 s 1 10 5 2s 1 10
b) Ask Usingabarmodel,whatexpressioncanyou
writefortheperimeterofthetrapezoid?2s 1
10 2 7 Can the expression be simplified? Yes, 2s 1
10 2 7 5 2s 1 3
c) Ask How do you find the perimeter of triangle
ABC? Substitute 7 for s in the expression 2s 1 10.
2s 1 10 5 2 3 7 1 10 5 24.
DAY 1
Write an addition or subtraction algebraic expression for a real-world problem and evaluate it.
56 advanced proofs not final pages
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Guided Practice
1
y 1 6
y 2 4
y ; 4; 12; 4
12; 8; 20
20
8
32 Chapter 7 Algebraic Expressions
b) How much gas is used if the car travels 5w miles? Evaluate this expression when
w 5 72.
5w miles
? groups
25 miles 25 miles 25 miles25 miles
25 miles 1 gallon
5w miles 5w 4 25 5 525w
gallons
525w
gallons of gas is used.
When w 5 72,
525w
5 5 72253
5 36025
5 14.4
Guided PracticeComplete.
2 A pick up truck uses 1 gallon of gas for every 14 miles traveled.
a) How far can it travel on 3p gallons of gas?
1 gallon
3p gallons
14 miles 14 miles 14 miles 14 miles
1 gallon ? miles
3p gallons ? 3 ? 5 ? miles
It can travel ___?___ miles on 3p gallons of gas.
Continue on next page
14
3p; 14; 42p
42p
30 Chapter 7 AlgebraicExpressions
Guided Practice1 Students who have difficulty
writing the expressions may not have
internalizedtheconceptthatletters
are used to represent numbers.
Assist these students by replacing
the letters with numbers and check if
they can then solve the problem.
Forc), encourage students to check
their answers by comparing the ages
theyfoundforKaylaandIsaacagainst
the facts in the original problem
statement. The ages they found
should make the statement true.
Since y 512,Raoulis12yearsold.
Kaylashouldbe18yearsold,and
Isaac should be 8 years old.
Learn
Model Useabarmodeltorepresentthescenarioina).
Ask What are you required to find in the problem? How
far the car can travel on w gallons of gas.
Ask Suppose the car can travel 25 miles on 1 gallon
of gas. What expression can you write that shows how
far the car can travel on 3 gallons of gas? 3 3 25 5 75
What expression can you write to show how far the car
can travel on w gallons of gas? w 3 25 5 25w
Explain Help students to see the relationship between
numbers and algebra. If students have difficulty
understanding the relationship in a), you may want to
set up a table showing gallons in one column and miles
traveled in a second column. Work with students to
fill out the table for 1 gallon, 2 gallons, 3 gallons, and
so on, so that they see the pattern of multiplying the
number of gallons (w) by 25.
Write a multiplication or division algebraic expression for a real-world problem and evaluate it.
Lesson 5 COUrse 1 • ChapTer 7
57advanced proofs not final pages
Teacher’s editio
n
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Guided Practice
1
y 1 6
y 2 4
y ; 4; 12; 4
12; 8; 20
20
8
32 Chapter 7 Algebraic Expressions
b) How much gas is used if the car travels 5w miles? Evaluate this expression when
w 5 72.
5w miles
? groups
25 miles 25 miles 25 miles25 miles
25 miles 1 gallon
5w miles 5w 4 25 5 525w
gallons
525w
gallons of gas is used.
When w 5 72,
525w
5 5 72253
5 36025
5 14.4
Guided PracticeComplete.
2 A pick up truck uses 1 gallon of gas for every 14 miles traveled.
a) How far can it travel on 3p gallons of gas?
1 gallon
3p gallons
14 miles 14 miles 14 miles 14 miles
1 gallon ? miles
3p gallons ? 3 ? 5 ? miles
It can travel ___?___ miles on 3p gallons of gas.
Continue on next page
14
3p; 14; 42p
42p
31Lesson 7.5 Real-WorldProblems:AlgebraicExpressions
Guided Practice2 In this problem, students can use
unit rates to understand whether they
write a multiplication expression or
division expression. In a), the answer
is in miles so multiply: miles per
gallon 3 gallons 5 miles.
Learn continued
b) Ask What are you required to find in the problem?
Amount of gas used if the car traveled 5w miles
What information in the problem can help you solve
the problem? To travel 25 miles, the car will need
1 gallon of gas.
Ask How much gas will be used after traveling
50 miles? 2 gallons How did you get the answer?
5025
3 1 What expression can you write for the
amount of gas used after traveling 5w miles?
525w
3 1 5
525w
gallons
Ask What do you need to do next? To evaluate the
expression when w = 72.
ExplainRemindstudentsofthemeaningof
“evaluate”.
Explain To evaluate 525w when w 5 72, students
need to substitute 72 for w in the expression 525w
.
Point out to students that they can evaluate 5w
before dividing by 25, the denominator.
Ask What answer do you get? 5 72253 5 14.4.
58 advanced proofs not final pages
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1
4
;v14
5614
v14
v; 14;v
14
34 Chapter 7 Algebraic Expressions
Guided PracticeComplete.
3 There were three questions in a mathematics test. Salma earned m points for the
first question and twice the number of points for the second question.
a) How many points did she earn for the first two questions?
First question:
points?
Second question:
points?
? 1 ? 5 ?
She earned ? points for the first two questions.
b) If she received a total of 25 points on the test, how many points did she
earn for the third question?
25 points
??
She earned ? points for the third question.
c) If m 5 5, find the points she earned for each question.
First question: m 5 5
Second question: 2m 5 2 3 ?
5 ?
Third question: 25 2 3m 5 25 2 (3 3 ? )
5 25 2 ?
5 ?
She earned ? points for the first question, ? points for the second
question and ? points for the third question.
m
2m
m; 2m; 3m
3m
3m
5
5
15
5; 10; 10
10
10
25 2 3m
32 Chapter 7 AlgebraicExpressions
Guided PracticeIn b), students divide:
miles miles per gallon 5 gallons.
Explain Ask students to think of a random number, say
5. Ask them to multiply it by 3 and then subtract 9 from
the product. Ask them for the answer. 6
Ask How did you find the answer? First,multiply5
by3.Next,subtract9fromtheproductof5and3.
Explain Look back at the question. Instead of the
number 5, you can replace it with the term y.Usingthe bar models, model for students the process of
multiplying y by 3 and then subtracting 9 from the
product.
Ask What expression do you get when you multiply the
term y by 3? 3y What expression do you get when you
subtract 9 from the product? 3y 2 9 What do you need
to do in the last part of the question? To evaluate the
expression when y 5 12
Explain Explaintheprocessofevaluatingexpressions.
Remindstudentstomultiplybeforesubtracting.
Learn
DAY 2
Write an algebraic expression using several operations and evaluate it.
Lesson 5 COUrse 1 • ChapTer 7
59advanced proofs not final pages
Teacher’s editio
n
Le
arn
1
4
;v14
5614
v14
v; 14;v
14
34 Chapter 7 Algebraic Expressions
Guided PracticeComplete.
3 There were three questions in a mathematics test. Salma earned m points for the
first question and twice the number of points for the second question.
a) How many points did she earn for the first two questions?
First question:
points?
Second question:
points?
? 1 ? 5 ?
She earned ? points for the first two questions.
b) If she received a total of 25 points on the test, how many points did she
earn for the third question?
25 points
??
She earned ? points for the third question.
c) If m 5 5, find the points she earned for each question.
First question: m 5 5
Second question: 2m 5 2 3 ?
5 ?
Third question: 25 2 3m 5 25 2 (3 3 ? )
5 25 2 ?
5 ?
She earned ? points for the first question, ? points for the second
question and ? points for the third question.
m
2m
m; 2m; 3m
3m
3m
5
5
15
5; 10; 10
10
10
25 2 3m
33Lesson 7.5 Real-WorldProblems:AlgebraicExpressions
Guided Practice3 In a), students build the algebraic
expression 3m by adding the
number of points. In b), they solve
the problem by using a part-whole
bar model. Point out that to find
a missing part, subtract. Guide
students to connect the pieces of
information given and found in a) and b) to solve c).
DIFFERENTIATED INSTRUCTION
Through Modeling
You may want to highlight the
relationship between the two
bars in a) and the bar model in b) by making the intermediate step
explicit. Have students use three
bars of equal length to model the
equation they completed in a): m 1 2m 5 3m. Point out that
their model for 3m matches one
of the bars of the bar model in b).
60 advanced proofs not final pages
Practice 7.5
1
2
3
4 14
Basic 1 – 3
Intermediate 4
Advanced 5 – 6
x 2 5
3x
24 years older
48y miles
(2x + 3) fruits
(90x + 150) cents
3x cm
3x cm
20 cm
39 cm2
x8
gallons
15x 1 252
cents
36 Chapter 7 Algebraic Expressions
5 José bought 4 comic books and 2 nonfiction books. The 4 comic books cost
him 8y dollars. If the cost of one nonfiction book is (3 1 7y) dollars more
expensive than the cost of one comic book, find
a) the cost of the 2 nonfiction books in terms of y.
b) the total amount that José spent on the books if y 5 4.
6 Wyatt has (2x 2 1) one-dollar bills and (4x 1 2) five-dollar bills. Susan has
3x dollars more than Wyatt.
a) Find the total amount of money that Wyatt has in terms of x.
b) Find the number of pens that Wyatt can buy if each pen costs 50¢.
c) If x 5 21, find how much money Susan will have now if Wyatt gives her
half the number of five-dollar bills that he has.
Find the perimeter of the figure in terms of x, given that all the angles in the
figure are right angles. If x 5 5.5, evaluate this expression.
16 cm
x cm
x cm
x cm
(22x 1 9) dollars
(18y 1 6) dollars
$110
(44x 1 18) pens
$749
(6x 1 32) cm; 65 cm
34 Chapter 7 AlgebraicExpressions
Practice 7.5
Assignment Guide
DAY 1 All students should
complete 1 – 2 .
DAY 2 All students should
complete 3 – 4 .
5 – 6 provide additional
challenge.
Optional: Extra Practice 7.5
1
2
3
Response to Intervention Lesson Check
Before assigning homework, use the following … to make sure students … Intervene with …
Exercises 1 and 2 • can solve a real-world problem using algebra
Reteach7.5• can write and evaluate expressions
Lesson 5 COUrse 1 • ChapTer 7
61advanced proofs not final pages
Teacher’s editio
n
Practice 7.5
1
2
3
4 14
Basic 1 – 3
Intermediate 4
Advanced 5 – 6
x 2 5
3x
24 years older
48y miles
(2x + 3) fruits
(90x + 150) cents
3x cm
3x cm
20 cm
39 cm2
x8
gallons
15x 1 252
cents
36 Chapter 7 Algebraic Expressions
5 José bought 4 comic books and 2 nonfiction books. The 4 comic books cost
him 8y dollars. If the cost of one nonfiction book is (3 1 7y) dollars more
expensive than the cost of one comic book, find
a) the cost of the 2 nonfiction books in terms of y.
b) the total amount that José spent on the books if y 5 4.
6 Wyatt has (2x 2 1) one-dollar bills and (4x 1 2) five-dollar bills. Susan has
3x dollars more than Wyatt.
a) Find the total amount of money that Wyatt has in terms of x.
b) Find the number of pens that Wyatt can buy if each pen costs 50¢.
c) If x 5 21, find how much money Susan will have now if Wyatt gives her
half the number of five-dollar bills that he has.
Find the perimeter of the figure in terms of x, given that all the angles in the
figure are right angles. If x 5 5.5, evaluate this expression.
16 cm
x cm
x cm
x cm
(22x 1 9) dollars
(18y 1 6) dollars
$110
(44x 1 18) pens
$749
(6x 1 32) cm; 65 cm
35Lesson 7.5 Real-WorldProblems:AlgebraicExpressions
Briefly describe a situation in
your classroom that can be
described algebraically. Then,
write an algebraic expression for
it.Finally,evaluatetheexpression
by substituting a realistic number
for the variable. Possible answer:
Tonight I have 3 times as many
math problems to do as I had last
night. Luckily, I have already done
4 problems. Algebraic expression:
3x 2 4. I had 6 problems to do
last night, so I substitute 6 for x
and solve: 3 3 6 2 4 5 14.
I have 14 problems left.
Also available on
TeacherOneStopCD-ROM.
Focusstudents’attentiononthe
vertical height of the figure. Guide
them to think of how they can get the
measurement of this vertical height.
Then, have students look at the
threehorizontalportionsofunknown
lengths. Ask students to figure out
what their sum is equal to. Then have
students solve the problem.
DIFFERENTIATED INSTRUCTION
Through Enrichment
Becauseallstudentsshouldbechallenged,haveallstudentstrytheBrain@Work
exercise on this page.
Foradditionalchallengingpracticeandproblemsolving,seeEnrichment, Course 1,
Chapter 7.
62 advanced proofs not final pages
Chapter Wrap up and review/Test CourSE 1 • CHAPTEr 7
Key Concepts
Chapter Wrap UpConcept Map
Algebraic Expressions
36 Chapter 7 AlgebraicExpressions
CHAPTER WRAP UP
Usethenotesandtheexamplesin
the concept map to review writing,
simplifying, evaluating, expanding,
and factoring algebraic expressions.
CHAPTER PROJECT
Towidenstudent’smathematical
horizonsandtoencouragethemto
think beyond the concepts taught in
this chapter, you may want to assign
the Chapter 7 project, available in
Activity Book, Course 1.
Vocabulary Review
Usethesequestionstoreviewchaptervocabularywith
students.
1. A letter used to represent a number is called a ? . variable
2. In the algebraic expression 2x 1 7, 2x and 7 are the ? of the expression. terms
3. When two expressions are equal for all values of
the variables, they are called ? ? . equivalent
expressions
4. In the expression 3y 1 y 1 6, the terms 3y and y are ? ? . like terms
5. In the expression 4x 2 5, 4 is the ? of x.
coefficient
AlsoavailableonTeacherOneStopCD-ROM.
63advanced proofs not final pages
Teacher’s editio
nChapter Wrap up and review/Test CourSE 1 • CHAPTEr 7
Key Concepts
Chapter Wrap UpConcept Map
Algebraic Expressions
38 Chapter 7 Algebraic Expressions
Chapter Review/TestConcepts and SkillsWrite an algebraic expression for each of the following.
1 A number that is 5 more than twice x.
2 The total cost, in dollars, of 4 pencils and 5 pens if each pencil costs w cents
and each pen costs 2w cents.
3 The length of a side of a square whose perimeter is r units.
4 The perimeter of a rectangle whose sides are of lengths (3z 1 2) units and
(2z 1 3) units.
Evaluate each expression for the given value of the variable.
5 3(x 1 4) 2 x2
when x 5 2 6 5 9
2p 1
1 2 5
3p 1
when p 5 5
Simplify each expression.
7 24k 1 11 2 5k 2 4 8 10 1 13h 2 6 2 4h 1 9 1 12h
Expand each expression.
9 5(m 1 3) 1 2(m 1 8) 10 9(x 1 2) 1 4(5 1 x)
Factor each expression.
11 5a 2 25 12 28 2 7x 13 12z 1 28 2 7z 2 3
State whether each pair of expressions are equivalent.
14 3(x 1 5) and 5(x 1 3) 15 6y 2 26 and 2(3y 2 13)
16 18 2 12p and 3(5 1 6p) 1 3(2p 1 1) 17 15 2 5q and 5(q 2 3 )
Problem SolvingSolve. Show your work.
18 Juan is g years old and Eva is 2 years younger than Juan.
a) Find the sum of their ages in terms of g.
b) Find the sum of their ages in g years’ time, in terms of g.
2x 1 5
(10z 1 10) units
7m 1 31
19k 1 7
5(a 2 5) 7(4 2 x) 5(z 1 5)
Equivalent
Not equivalent
Not equivalent
Not equivalent
2g 2 2
4g 2 2
13x 1 38
13 1 21h
17 22
7w50
dollarsr4
units
37Chapter 7 AlgebraicExpressions
TEST PREPARATION
Foradditionaltestprep
Examview Assessment Suite
CD-ROM Course 1
CHAPTER REVIEW/TEST
Chapter Assessment
UsetheChapter7Testin
Assessments, Course 1 to assess
how well students have learned
the material in this chapter. This
assessment is appropriate for
reporting results to adults at
home and administrators.
1
2
3
Response to Intervention Use the table for reteaching recommendations.
Exercises Intervene with Reteach worksheet…
1 to 4 7.1 Writing algebraic expressions
5 to 6 7.2 Evaluatingalgebraicexpressions
7 to 8 7.3 Simplifying algebraic expressions
9 to 17 7.4 Expandingandfactoringalgebraicexpressions
18 to 24 7.5 Solving real-world problems involving algebraic expressions
64 advanced proofs not final pages
Chapter review/Test COUrse 1 • ChapTer 7
19
20
21
22
23
24
60t
chairs7t20
chairs
(4p 2 5) marbles
(h 2 4) muffins
(8y 1 8) m
(7m 1 10) yards
31 yards
(11p 2 4) quarts
84 quarts
5 liters
38 Chapter 7 AlgebraicExpressions
advanced proofs not final pages64
Grades 1–5
65
scope and sequence
advanced proofs not final pages
MIF Scope and Sequence GrADES 4–6
Grade 4 Grade 5 Grade 6 (COuRSE 1)
Number and operations
sets and Numbers
explore negative numbers in context
Understand the systems of integers and rational numbers
Number representa-tion
represent numbers to 100,000
represent numbers to 10,000,000
represent negative numbers on a number line
represent whole numbers using roots and exponents (squares and cubes only)
represent the absolute value of a number
Compare and order
compare and order whole numbers to 100,000
compare and order decimal numbers
compare and order whole numbers to 10,000,000
compare and order integers and rational numbers using < and >
Place Value express numbers to 100,000 in three forms
express numbers to 10,000,000 in various forms
apply place value concepts in standard algorithms
Fraction Concepts
recognize, write, and name mixed numbers and improper fractions
Find a fraction of a set, equivalent fractions, and equivalent mixed numbers/ improper fractions
convert fractions to decimals
relate fraction and division expressions
recognize, name, and write positive and negative integers and rational numbers
66 advanced proofs not final pages
Scope and Sequence GrADES 4–6
Grade 4 Grade 5 Grade 6 (COuRSE 1)
Number and operations (continued)
Decimal Concepts
model decimals using tenths and hundredths
Understand decimal notation (hundredths) as an extension of the base-ten system
read and write decimals that are greater than 1 and less than 1
compare and order decimal numbers
identify equivalent decimals and fractions
model decimal numbers using thousandths
Understand place value concepts through thousandths
convert decimals to fractions
apply place value concepts in standard algorithms
convert decimals to fractions and percents.
ratio and Proportion
Understand concept of ratio
Use ratios to solve problems
Find equivalent ratios
solve problems involving unit rates and speed
construct tables of equivalent ratios and plot them on coordinate plane
recognize linear relationship of plotted pairs of equivalent ratios
Use proportional reasoning to draw conclusions and predict relative frequencies of outcomes for situations involving randomness
Grades 1–5
67
scope and sequence
advanced proofs not final pages
Grade 4 Grade 5 Grade 6 (COuRSE 1)
Number and operations (continued)
Percents solve problems with percents
convert fractions to percents
Find a percent of a number
Write fractions and decimals as percents
Find the whole, given a percentage and a percent
solve multi-step problems involving simple interest, tax, percent increase or decrease, percent error
Whole Number Computation: Multiplication and Division
apply an understanding of models of multiplication and division
recall multiplication facts and related division facts
develop fluency in multiplying multi-digit numbers
divide by a 1-digit number with a remainder
solve multi-digit multiplication and division problems
multiply multi-digit numbers
Find quotients involving multi-digit dividends
solve whole-number multiplication and division problems
select the most useful form of the quotient and interpret the remainder
Find whole-number quotients involving multi-digit divisors
Find factors of whole numbers, square roots of perfect squares, and cube roots of perfect cubes
Find the greatest common factor or least common multiple of two whole numbers
68 advanced proofs not final pages
Scope and Sequence GrADES 4–6
Grade 4 Grade 5 Grade 6 (COuRSE 1)
Number and operations (continued)
Fraction Computation
add and subtract unlike fractions that have related denominators
add and subtract unlike fractions and mixed numbers
multiply proper fractions, improper fractions, mixed numbers, and whole numbers
divide fractions by whole numbers
solve word problems by adding, subtracting, multiplying, and dividing fractions
divide whole numbers, fractions, and mixed numbers by fractions
solve word problems by adding, subtracting, multiplying, and dividing fractions
Decimal Computation
add and subtract decimal numbers
solve problems by adding and subtracting decimals
add and subtract decimals to the thousandths place
multiply and divide decimals by whole numbers
solve problems by multiplying and dividing decimals
multiply and divide decimals by decimals
solve problems by multiplying and dividing decimals
estimation and Mental Math
Use mental math and estimation strategies to find sums, differences, products, and quotients
decide whether an estimate or an exact answer is needed
estimate relative sizes of amounts or distances
round and estimate with decimals
Use mental math and estimation strategies to find sums, differences, products, and quotients
estimate sums and differences of fraction and decimal operations
estimate products and quotients with decimals
estimate to check reasonableness of fraction and decimal computations
Grades 1–5
69
scope and sequence
advanced proofs not final pages
Grade 4 Grade 5 Grade 6 (COuRSE 1)
Algebra
Patterns identify, describe, and extend numeric and nonnumeric patterns
Use a rule to describe a sequence of numbers or objects
identify, describe, and extend numeric patterns involving all operations
Find a rule to complete a number pattern
construct and analyze tables of quantities in equivalent ratios and use equations to describe the relationship
Properties represent division as the inverse of multiplication
Write equivalent algebraic expressions by applying number properties
Number Theory
Find the greatest common factor and least common multiple of two numbers
identify prime and composite numbers
Write prime factorization of whole numbers
apply prime factorizations to finding square roots, cube roots, GcF, and lcm
Functional relationships
Understand the relationships between the numbers and symbols in formulas for area and perimeter
describe number relationships in context
Understand the relationships between the numbers and symbols in formulas for surface area and volume
describe number relationships in context
Use variables to represent two varying quantities in a given context
identify independent and dependent variables
express the relationship between two quantities as an equation
Graphing Functions
Graph equations from function tables
Graph data given in a table, such as conversion of °F to °c or equivalent ratios
70 advanced proofs not final pages
Scope and Sequence GrADES 4–6
Grade 4 Grade 5 Grade 6 (COuRSE 1)
Algebra (continued)
expressions/ Models
Use a variety of concrete, pictorial, and symbolic models for multiplication and division; and addition and subtraction with fractions and decimals
Use letters as variables
simplify algebraic expressions
Use the order of operations in numeric expressions with two or more operations
Use, write, and interpret conventions of algebraic notation, including order of operations (including exponents)
evaluate expressions given specific values for variables
Write equivalent expressions using number properties
Number sentences and equations
Write and solve number sentences for one-, two-, and three-step real-world problems
Use bar models and number sentences for one-, two-, and three-step problems
determine the missing parts (quantities or symbols) in number sentences
Write and solve number sentences and equations for one- and two-step real-world problems
Write and solve one- and two-step equations
solve linear equations of the form x + p = q, p < q, using properties of equality informally
Find unknown quantities in problems involving equal ratios
Write equations and inequalities to solve problems in context
equality and Inequality
Understand equality and inequality
Understand equality and inequality
Understand and apply the properties of equality informally
represent solutions to inequalities of the form x > c or x ≤ c on a number line
Grades 1–5
71
scope and sequence
advanced proofs not final pages
Grade 4 Grade 5 Grade 6 (COuRSE 1)
Geometry
Lines and Angles
draw perpendicular and parallel lines
construct and measure angles
solve problems involving angles on a straight line
solve problems involving angles about a point
Polygons apply the properties of squares and rectangles
Find unknown angle measures and side lengths of squares and rectangles
identify figures that form tessellations
Understand the relationships between the numbers and symbols in formulas for area and perimeter
apply the properties of right, isosceles, and equilateral triangles
apply the sum of the angle measures of a triangle formula
apply the properties of a parallelogram, rhombus, and trapezoid
show that the sum of any two side lengths of a triangle is greater than the length of the third
Find the area of a triangle
identify polygons in the coordinate plane
Find area of polygons by decomposition into triangles
derive area formula of special quadrilaterals by decomposition and reassembly
solve word problems involving area of plane figures
72 advanced proofs not final pages
Scope and Sequence GrADES 4–6
Grade 4 Grade 5 Grade 6 (COuRSE 1)
Geometry (continued)
Circles identify the parts of a circle
relate the radius of a circle to its diameter, circumference, and area
calculate the circumferences and areas of circles, semicircles, and quarter circles
solid Figures identify and classify prisms and pyramids
identify the solid that can be formed from a given net
identify cylinders, spheres, and cones
describe cylinders, spheres, and cones by the number and types of faces, edges, and vertices
Find volume of a prism with a uniform cross-section base
Find the surface areas of cubes, prisms, and pyramids
explore rectangular prisms with same surface area and different volumes
explore rectangular prisms with same volume and different surface areas
Grades 1–5
73
scope and sequence
advanced proofs not final pages
Grade 4 Grade 5 Grade 6 (COuRSE 1)
Geometry (continued)
Congruence and symmetry
identify line and rotational symmetry
relate rotational symmetry to turns and congruency
Transforma-tions
Use transformations to form tessellations
Coordinate Geometry
develop coordinate readiness with tables and line graphs
Plot points on a coordinate grid (first quadrant only)
Plot points on a coordinate grid (all four quadrants)
draw polygons in the coordinate plane, given coordinates of the vertices
Find distance between two points with the same x-coordinate or the same y-coordinate
74 advanced proofs not final pages
Scope and Sequence GrADES 4–6
Grade 4 Grade 5 Grade 6 (COuRSE 1)
Measurement
Angles estimate and measure angles with a protractor
classify angles by angle measures
relate ¼-, ½-, ¾-, and full turns to the number of right angles
apply the sum of the angles in a straight line to solve problems
apply the vertical angles property of intersecting lines
apply the sum of the angles about a point to solve problems
Perimeter and Circumference
Find the perimeter of composite figures
solve problems involving the perimeter of squares, rectangles, and composite figures
solve problems involving the perimeter of squares, rectangles, and composite figures
Give an informal derivation of the formula relating the radius and circumference of a circle
calculate circumferences of circles, semicircles, and quarter circles
Grades 1–5
75
scope and sequence
advanced proofs not final pages
Grade 4 Grade 5 Grade 6 (COuRSE 1)
Measurement (continued)
Area identify area as an attribute of two-dimensional figures
connect area formula for a rectangle to the area model for multiplication
estimate area in square units
compare the areas and perimeters of two-plane figures
Find the area of rectangles and composite figures
Find the area of triangles Find area of polygons by decomposing them into triangles
derive area formulas for special quadrilaterals by decomposition and reassembly
derive formula for area of a circle
solve word problems involving area of plane figures
surface Area and Volume
Use the net of a prism to find its surface area
estimate and measure volume in cubic units
Find surface area of cubes, prisms, and pyramids
Find volume of prisms with uniform cross-section base
exhibit prisms with different surface areas but same volumes and vice versa
solve word problems involving solids
76 advanced proofs not final pages
Scope and Sequence GrADES 4–6
Grade 4 Grade 5 Grade 6 (COuRSE 1)
Data Analysis
Classifying and sorting
construct line plots, stem-and-leaf plots, tables, and line graphs
represent data in a double bar graph
collect data and summarize the results using tables
represent appropriate data using dot plots (scatter plots), histograms, and box plots
Interpret/ Analyze Data
interpret tally charts, bar graphs, picture graphs, tables, and line graphs
Find the mean (average), median, mode, and range of a data set
analyze data in a double bar graph
describe and summarize distributions of data
measure the center of a data set as a single number that describes all the values of the set
Find the mean, median, range, and interquartile range of a given set of data
measure variation as a single number that describes how the values of a numerical data set vary
Grades 1–5scope and sequence
advanced proofs not final pages 77
Grade 4 Grade 5 Grade 6 (COuRSE 1)
Probability
outcomes decide whether an outcome is certain, more likely, equally likely, less likely, or impossible
Find all possible outcomes of a compound event by listing, making a tree diagram, or multiplying
expressing Probability
express the probability of an event as a fraction
determine the experimental probability of a simple event
compare the results of an experiment with the theoretical probability
Math in Focus CourSE 1
CoMPoNeNTsstudent Books A and Bwith full examples, guided practice, and hands-on activities
Teacher’s editions A and Breteach, enrichment, and extra Practice
Transition Guide and online resource Map for comprehensive transition support and guidance with access to previous grade material
Assessments
solutions Key
online student Book and Teacher’s edition
Interactive Whiteboard Lessons
Activity Book
Test Generator powered by examview®
Manipulative Kit
Virtual Manipulatives
online resources for Teachers, students, and Parents
Program Components
78
Grades 1–5
7979
80
Notes
advanced proofs not final pages
Grades 1–5
81advanced proofs not final pages
ArrivingFall 2011
Course 3
A
ArrivingFall 2012
Course 2
A
ArrivingFall 2012
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