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Chapter 12 Skills Practice • 737
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Lesson 12.1 Skills Practice
Name ________________________________________________________ Date _________________________
Willie CatchemAnalyzing Problem Situations Using Multiple Representations
Problem SetWrite an equation that represents the relationship shown in each table. Use the equation
to answer the question.
1. Terell is biking around a track. The table show the time it takes Terell to complete several laps
around the track. Write an equation that represents the relationship shown in the table. If Terell
bikes around the track for 1 hour, how many laps will he complete?
Time (minutes) Distance (laps)
0 0
12 9
24 18
Let t 5 time (minutes)
Let d 5 distance (laps)
speed 5 9 laps ___________
12 minutes
5 0.75 lap per minute
d 5 0.75t
1 hour 5 60 minutes
d 5 0.75t
5 0.75(60)
5 45
If Terell bikes around the track for 1 hour, he will complete 45 laps.
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Lesson 12.1 Skills Practice page 2
2. Claudia is jogging around her neighborhood. The table shows the distance Claudia travels during
her jog. Write an equation that represents the relationship shown in the table. How long will it take
Claudia to jog 5 miles?
Time (hours) Distance (miles)
0 0
0.5 1.5
0.75 2.25
Chapter 12 Skills Practice • 739
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Lesson 12.1 Skills Practice page 3
Name ________________________________________________________ Date _________________________
3. Shawna is driving to the beach for summer vacation. The table shows the distance Shawna travels
during her trip. Write an equation that represents the relationship shown in the table. How long will
it take Claudia to drive the entire 500 mile trip?
Time (hours) Distance (miles)
0 0
2 110
3 165
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Lesson 12.1 Skills Practice page 4
4. Mattie and Lavonne agree to meet and make signs for the pep rally. Lavonne starts 30 minutes
early and completes 2 signs before Mattie arrives. The table shows the total number of signs the
girls have completed at different times after Mattie arrives. Write an equation that represents the
relationship shown in the table. If the girls work for 3 hours after Mattie arrives, what is the total
number of signs the girls will complete?
Time (hours) Number of Signs
20.5 0
0 2
0.5 4
Chapter 12 Skills Practice • 741
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Lesson 12.1 Skills Practice page 5
Name ________________________________________________________ Date _________________________
5. Juan leaves his home and rides his bike for 15 minutes to the park. After he gets to the park, he
resets his odometer to 0 and continues to ride at the same speed. The table shows the distance
Juan traveled at the park according to his odometer. Write an equation that represents the
relationship shown in the table. If it has been 1.5 hours since Juan left home, what is the distance
he rode his bike at the park?
Time (hours) Distance (miles)
0.25 0
0.5 1.25
0.75 2.5
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Lesson 12.1 Skills Practice page 6
6. Lee is a member of the drama club. He is setting up chairs in the gym for the school play. He
arrives 5 minutes early and sets up 25 chairs before Jin arrives to help. The table shows the total
number of chairs set up at different times after Jin arrives. Write an equation that represents the
relationship shown in the table. If Lee and Jin continue at the same pace, how long will it take to
set up 300 chairs?
Time (minutes) Number of Chairs
25 0
0 25
10 75
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Lesson 12.1 Skills Practice page 7
Name ________________________________________________________ Date _________________________
Complete each table using the given equation. Use the table to graph the equation.
7. Joelle is ice skating around an ice rink. The equation d 5 0.5t represents the relationship between
the time Joelle skates in minutes, t, and the distance she skates in laps, d. Complete the table.
Graph the points on the grid.
Time (minutes) Distance (laps)
0 0
10 5
20 10
30 15
-30
-40
-30-40-50
Dis
tanc
e (la
ps)
-20 -10
Time (minutes)
0 10 20 30 40 50
x
y
-10
0
10
20
30
40
-50
-20
50
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Lesson 12.1 Skills Practice page 8
8. Leon is jogging around a park. The equation d 5 5t represents the relationship between the time
Leon jogs in hours, t, and the distance he jogs in miles, d. Complete the table. Graph the
points on the grid.
Time (hours) Distance (miles)
0
0.25
2.5
1
-3
-4
-1.5-2.0-2.5
Dis
tanc
e (m
iles)
-1.0 -0.5
Time (hours)
0 0.5 1.0 1.5 2.0 2.5-1
0
1
2
3
4
-5
-2
5
x
y
Chapter 12 Skills Practice • 745
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Lesson 12.1 Skills Practice page 9
Name ________________________________________________________ Date _________________________
9. Perry is driving to college. The equation d 5 60t represents the relationship between the time
Perry travels in hours, t, and the distance he travels in miles, d. Complete the table. Graph the
points on the grid.
Time (hours) Distance (miles)
0
1
2
180
-120
-160
-3-4-5
Dis
tanc
e (m
iles)
-2 -1
Time (hours)
0 1 2 3 4 5-40
0
40
80
120
160
-200
-80
200
x
y
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Lesson 12.1 Skills Practice page 10
10. Elesha and Jada are making greeting cards to send to the children’s hospital. Jada makes 2 cards
before Elesha arrives to help. The equation c 5 2 1 8t represents the relationship between the
time Elesha and Jada make cards in hours, t, and the number of cards they make, c. Complete the
table. Graph the points on the grid.
Time (hours) Number of Cards
0
0
0.5
1
-6
-8
Num
ber
of C
ard
s
Time (hours)
0
-2
0
2
4
6
8
-10
-4
10
-1.5-2.0-2.5 -1.0 -0.5 0.5 1.0 1.5 2.0 2.5
x
y
Chapter 12 Skills Practice • 747
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Lesson 12.1 Skills Practice page 11
Name ________________________________________________________ Date _________________________
11. Ling leaves her home and walks for 15 minutes to the park. After she gets to the park, she
resets her pedometer to 0 and continues to walk at the same speed. The equation d 5 2t 2 0.5
represents the relationship between the time Li walks in hours, t, and the distance she walks in the
park in miles, d. Complete the table. Graph the points on the grid.
Time (hours) Distance (miles)
0
0
0.5
0.75
-1.5
-2.0
Dis
tanc
e (m
iles)
Time (hours)
0
-0.5
0
0.5
1.0
1.5
2.0
-2.5
-1.0
2.5
-1.5-2.0-2.5 -1.0 -0.5 0.5 1.0 1.5 2.0 2.5
x
y
748 • Chapter 12 Skills Practice
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Chapter 12 Skills Practice • 749
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Pony ExpressInterpreting the Standard Form of a Linear Equation
Problem SetWrite an expression to represent each problem situation. Evaluate the expression to answer the
question.
1. Aiko is walking 2 miles per hour. How far will she walk in 3 hours?
Let x equal the number of hours Aiko walks.
The expression 2x represents the distance Aiko walks in miles.
2x 5 2(3)
5 6 miles
Aiko will walk 6 miles in 3 hours.
2. Isabel is jogging 4 miles per hour. How long will it take her to jog 6 miles?
Lesson 12.2 Skills Practice
Name ________________________________________________________ Date _________________________
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Lesson 12.2 Skills Practice page 2
3. Chen is biking 6 miles per hour. How far will he travel in 2 hours?
4. Lamar is sketching people’s faces at the spring carnival. He can create 6 sketches per hour.
How many sketches can he create in 4 hours?
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Lesson 12.2 Skills Practice page 3
Name ________________________________________________________ Date _________________________
5. Luis is shoveling snow from driveways in his neighborhood to save money for college. He can
shovel 2 driveways per hour. How long will it take Luis to shovel 8 driveways?
6. Darell is mowing lawns to save money for summer vacation. He can mow 1.5 lawns per hour.
How many lawns can he mow in 6 hours?
752 • Chapter 12 Skills Practice
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Lesson 12.2 Skills Practice page 4
Write an expression to represent each problem situation.
7. Eva and Sofia are participating in a relay for charity. Eva jogs 4 miles per hour. Sofia walks
2 miles per hour. Write an expression that represents the distance that Eva and Sofia travel
during the relay.
Let x equal the number of hours Eva jogs.
The expression 4x represents the distance Eva jogs in miles.
Let y equal the number of hours Sofia walks.
The expression 2y represents the distance Sofia walks in miles.
The expression 4x 1 2y represents the distance that Eva and Sofia travel during the relay.
8. Nina and Olivia are taking turns painting portraits at the spring carnival. Nina paints 3 portraits
per hour. Olivia paints 2 portraits per hour. Write an expression that represents the number of
portraits that Nina and Olivia paint during the carnival.
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Lesson 12.2 Skills Practice page 5
Name ________________________________________________________ Date _________________________
9. Teresa and Juanita volunteer to take turns making signs for the football game. Teresa makes
8 signs per hour. Juanita makes 6 signs per hour. Write an expression that represents the number
of signs that Teresa and Juanita make for the football game.
10. Geraldo and Raul are participating in a relay for charity. Geraldo rides his bike 6 miles per hour.
Raul rides his bike 5 miles per hour. Write an expression that represents the distance that Geraldo
and Raul travel during the relay.
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Lesson 12.2 Skills Practice page 6
11. Nelson and Ronna volunteer to take turns cleaning up the bike path at the park. Nelson cleans
1 mile per hour. Ronna cleans 2 miles per hour. Write an expression that represents the distance
that Nelson and Ronna clean.
12. Denisa and Tonya take turns making bead necklaces to sell at a school fundraiser. Denisa makes
2 necklaces per hour. Tonya makes 3 necklaces per hour. Write an expression that represents the
number of necklaces that Denisa and Tonya make for the school fundraiser.
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Lesson 12.2 Skills Practice page 7
Name ________________________________________________________ Date _________________________
Write an equation to represent each problem situation. Solve the equation to answer the question.
Check your answer.
13. The expression 3x 1 2y represents the distance that Shanise and Kiana travel during a 12 mile
relay for charity. Let x represent the number of hours Shanise walks and let y represent the number
of hours that Kiana walks. If Shanise walks for 2.5 hours, how many hours must Kiana walk?
Check:
3x 1 2y 5 12 3x 1 2y 5 12
3(2.5) 1 2(2.25) 0 12
7.5 1 4.5 0 12
12 5 12
3(2.5) 1 2y 5 12
7.5 1 2y 5 12
2y 5 4.5
y 5 2.25
Kiana must walk 2.25 hours.
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Lesson 12.2 Skills Practice page 8
14. The expression 2x 1 4y represents the number of portraits that Nina and Olivia paint while taking
turns at the spring carnival. They expect to paint 30 portraits at the carnival. Let x equal the
number of hours Nina paints. Let y equal the number of hours Olivia paints. If Olivia paints for
4.5 hours, how long must Nina paint to complete the 30 portraits?
15. The expression 5x 1 6y represents the number of signs that Joelle and Mattie make for the
basketball game. They plan to take turns to make 25 signs. Let x equal the number of hours
Joelle makes signs. Let y equal the number of hours Mattie makes signs. If Joelle makes signs for
2 hours, how long must Mattie make signs?
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Lesson 12.2 Skills Practice page 9
Name ________________________________________________________ Date _________________________
16. The expression 6x 1 5.5y represents the distance that Carlos and Leon travel during a 20 mile
relay for charity. Let x equal the number of hours Carlos rides his bike. Let y equal the number of
hours Leon rides his bike. If Leon rides his bike for 2 hours, how long must Carlos ride his bike to
complete the relay?
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Lesson 12.2 Skills Practice page 10
17. The expression 1.5x 1 2y represents the distance that Perry and Ty cover while volunteering to
clean up the bike path at the park. The bike path is 8 miles long. Let x equal the number of hours
Perry cleans the bike path. Let y equal the number of hours Ty cleans the bike path. If Perry cleans
for 3 hours, how long must Ty clean?
18. The expression 4x 1 3.5y represents the number of necklaces that Denisa and Tonya make for the
school fundraiser. They plan to make 30 necklaces. Let x equal the number of hours Denisa makes
necklaces. Let y equal the number of hours Tonya makes necklaces. If Tonya makes necklaces for
4 hours, how long must Denisa make necklaces?
Chapter 12 Skills Practice • 759
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Lesson 12.3 Skills Practice
Name ________________________________________________________ Date _________________________
Slopes, Forms, Graphs, and InterceptsConnecting the Standard Form with the Slope-Intercept Form of Linear Functions
Problem SetComplete each table using the equation in standard form to determine the x-intercept and y-intercept.
Calculate the slope. Graph the equation.
1. 2x 1 4y 5 12
x y Work
0 3
2x 1 4y 5 12
2(0) 1 4y 5 12
4y 5 12
y 5 3
6 0
2x 1 4y 5 12
2x 1 4(0) 5 12
2x 5 12
x 5 6
760 • Chapter 12 Skills Practice
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Lesson 12.3 Skills Practice page 2
y-intercept: (0, 3)
-6
-8
0
-2
0
2
4
6
8
-10
-4
10
-6-8-10 -4 -2 2 4 6 8 10
y
x
x-intercept: (6, 0)
slope 5 3 2 0 ______ 0 2 6
5 3 ___ 26
5 2 1 __ 2
2. 3x 2 5y 5 30
x y Work
0
0
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Lesson 12.3 Skills Practice page 3
Name ________________________________________________________ Date _________________________
-6
-8
0
-2
0
2
4
6
8
-10
-4
10
-6-8-10 -4 -2 2 4 6 8 10
y
x
3. 4x 1 2y 5 14
x y Work
0
0
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Lesson 12.3 Skills Practice page 4
-6
-8
0
-2
0
2
4
6
8
-10
-4
10
-6-8-10 -4 -2 2 4 6 8 10
y
x
4. 3x 2 4y 5 224
x y Work
0
0
Chapter 12 Skills Practice • 763
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Lesson 12.3 Skills Practice page 5
Name ________________________________________________________ Date _________________________
-6
-8
0
-2
0
2
4
6
8
-10
-4
10
-6-8-10 -4 -2 2 4 6 8 10
y
x
5. 22x 1 3y 5 27.5
x y Work
0
0
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Lesson 12.3 Skills Practice page 6
-6
-8
0
-2
0
2
4
6
8
-10
-4
10
-6-8-10 -4 -2 2 4 6 8 10
y
x
6. 2x 2 0.5y 5 4
x y Work
0
0
Chapter 12 Skills Practice • 765
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Lesson 12.3 Skills Practice page 7
Name ________________________________________________________ Date _________________________
-6
-8
0
-2
0
2
4
6
8
-10
-4
10
-6-8-10 -4 -2 2 4 6 8 10
y
x
Convert each equation in standard form to slope-intercept form.
7. 5x 1 6y 5 60
5x 1 6y 5 60
5x 2 5x 1 6y 5 25x 1 60
6y 5 25x 1 60
6y
___ 6
5 25x 1 60 _________ 6
y 5 2 5 __ 6 x 1 10
8. 2x 1 8y 5 216
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Lesson 12.3 Skills Practice page 8
9. 210x 1 15y 5 45
11. 18x 2 3y 5 6
10. 8x 1 2y 5 14
12. 3x 1 2y 5 10
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Lesson 12.3 Skills Practice page 9
Name ________________________________________________________ Date _________________________
Convert each equation in slope-intercept form to standard form.
13. y 5 1 __ 4
x 1 9
y 5 1 __ 4
x 1 9
4y 5 4 ( 1 __ 4 x 1 9 )
4y 5 x 1 36
2x 1 4y 5 x 2 x 1 36
2x 1 4y 5 36
15. y 5 3x 2 2
14. y 5 28x 1 3
16. y 5 2 2 __ 3 x 1 1
768 • Chapter 12 Skills Practice
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Lesson 12.3 Skills Practice page 10
17. y 5 2 5 __ 2 x 2 6 18. y 5 29x 2 2
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Lesson 12.4 Skills Practice
Name ________________________________________________________ Date _________________________
The Journey Starts with a Single Step—But There Are Many Steps After That!Intervals of Increase, Decrease, and No Change
VocabularyChoose the term or phrase from the box that correctly completes each sentence.
constant function increasing function decreasing function
interval of increase interval of decrease constant interval
1. When the value of a dependent variable decreases as the independent variable increases, the
function is said to be a(n) .
2. When both the dependent and independent values of a function increase, the function is said to
be a(n) .
3. When a function is decreasing for some values of the independent variable, it is said to have
a(n) .
4. When the dependent variable does not change as the independent value of a function increases,
the function is said to be a(n) .
5. When a function is constant for some values of the independent variable, it is said to have
a(n) .
6. When a function is increasing for some values of the independent variable, it is said to have
a(n) .
770 • Chapter 12 Skills Practice
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Lesson 12.4 Skills Practice page 2
Problem SetIdentify each function displayed in each graph as an increasing function, a decreasing function, or a
constant function.
1. y
x
2. y
x
decreasing function
3. y
x
4. y
x
Chapter 12 Skills Practice • 771
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Lesson 12.4 Skills Practice page 3
Name ________________________________________________________ Date _________________________
5. y
x
6. y
x
Identify each interval of increase, the interval of decrease, and the constant interval as appropriate for
the function shown in each graph.
7.
00
2
1
4
3
6
7
5
8
9
10
21 43 65 87 109
y
x
Constant interval: The function is constant
from 0 to 3.
Interval of increase: The function is
increasing from 3 to 5.5.
Interval of decrease: The function is
decreasing from 5.5 to 8.5.
772 • Chapter 12 Skills Practice
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Lesson 12.4 Skills Practice page 4
8.
00
20
10
40
30
60
70
50
80
90
100
2010 4030 6050 8070 10090
y
x
9.
-6
-8
0
-2
0
2
4
6
8
-10
-4
10
-6-8-10 -4 -2 2 4 6 8 10
y = |x - 4|
y
x
Chapter 12 Skills Practice • 773
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Lesson 12.4 Skills Practice page 5
Name ________________________________________________________ Date _________________________
10.
-6
-8
0
-2
0
2
4
6
8
-10
-4
10
-6-8-10 -4 -2 2 4 6 8 10
y
x
y = -|x + 2|
11.
00
4
2
8
6
12
14
10
16
18
20y
x42 86 1210 1614 2018
774 • Chapter 12 Skills Practice
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Lesson 12.4 Skills Practice page 6
12.
00
8
4
16
12
24
28
20
32
36
40
84 1612 2420 3228 4036
y
x
Define variables and write an equation (or equations) to represent the problem situation. Graph the
equation (or equations).
13. Noah walks from home to school at a rate of 5 feet per second. It takes Noah 15 minutes to walk
to school. Write an equation that represents Noah’s distance from home. Graph the equation.
Let t 5 time in seconds
00
1000
Dis
tanc
e Fr
om H
ome
(in fe
et)
500
2000
1500
3000
3500
2500
4000
4500
5000
200100 400
Time (in seconds)
300 600500 800700 1000900
y
x
Let d 5 distance from home in feet
15 minutes 5 15(60)
5 900 seconds
d 5 5t
d 5 5(900)
d 5 4500
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Lesson 12.4 Skills Practice page 7
Name ________________________________________________________ Date _________________________
14. Mario is at school, 3500 feet from his home. He stays there for 2 hours. Write an equation that
represents Mario’s distance from home. Graph the equation.
00
1000
500
2000
1500
3000
3500
2500
4000
4500
5000
1 2 3 4 5
y
x
776 • Chapter 12 Skills Practice
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Lesson 12.4 Skills Practice page 8
15. Hector is at school, 7200 feet from home. He leaves school and rides his bike home at
a rate of 12 feet per second. Write an equation that represents Hector’s distance from home.
Graph the equation.
0 1000
1600
800
3200
2400
4800
5600
4000
6400
7200
8000
200 300 400 500 600 700 800 900 1000
y
x
Chapter 12 Skills Practice • 777
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Lesson 12.4 Skills Practice page 9
Name ________________________________________________________ Date _________________________
16. Rita walks from home to the store at a rate of 6 feet per second. It takes her 10 minutes to walk
to the store. After arriving at the store, she stays for 30 minutes. Write an equation that represents
Rita’s distance from home. Graph the equation.
0 4000
800
400
1600
1200
2400
2800
2000
3200
3600
4000
800 1200 1600 2000 2400 2800 3200 3600 4000
y
x
778 • Chapter 12 Skills Practice
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Lesson 12.4 Skills Practice page 10
17. Elena is at Lea’s house, which is 3600 feet from Elena’s home. Elena leaves Lea’s house and
walks in the direction toward her home at a rate of 5 feet per second. After 8 minutes, she stops
at Cristina’s house. She stays at Cristina’s house for 30 minutes. Write an equation that represents
Elena’s distance from home. Graph the equation.
0 4000
800
400
1600
1200
2400
2800
2000
3200
3600
4000
800 1200 1600 2000 2400 2800 3200 3600 4000
y
x
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Lesson 12.4 Skills Practice page 11
Name ________________________________________________________ Date _________________________
18. Nina is at her friend Maria’s house 9000 feet from home. She stays at Maria’s house for 1 hour.
Nina then rides her bike home at a rate of 10 feet per second. Write an equation that represents
Nina’s distance from home. Graph the equation.
0 4500
1800
900
3600
2700
5400
6300
4500
7200
8100
9000
900 1350 1800 2250 2700 3150 3600 4050 4500
y
x
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Chapter 12 Skills Practice • 781
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Piecewise FunctionsDeveloping the Graph of a Piecewise Function
VocabularyDefine the term in your own words.
1. piecewise function
Problem SetWrite a piecewise function from each table or context.
1. Minutes 0 1 10 20 40 41 50
Gallons of Water in Tub 0 2 20 40 40 36 0
2x, 0 # x # 20
f(x) 5 40, 20 , x # 40
200 2 4x, 40 , x # 50
Lesson 12.5 Skills Practice
Name ________________________________________________________ Date _________________________
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Lesson 12.5 Skills Practice page 2
2. At 10:00, Sheila biked to Jill’s house. She stayed at Jill’s for an hour. Then, she biked back home.
Sheila can bike 10 miles per hour uphill and 20 miles per hour downhill. (Hint: Use minutes as the
x-value.)
Sheila’s house
10 Miles
Jill’s house
3. Kyle saved $4 per day for 30 days. Then, he spent $5 a day for 8 days. After that he started saving
again at a rate of $3 per day for 22 days.
4. Hours 0 2 5 6 7 8 10
Miles Driven 0 140 350 395 460 525 655
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Lesson 12.5 Skills Practice page 3
Name ________________________________________________________ Date _________________________
5. Miles received a $50 gift card to an online music store from his aunt. He decided to spend a certain
amount each day to extend his enjoyment of the gift card. For the first three days, he set his limit
for $5 per day. Then, he was worried it wouldn’t last long enough at that rate, so he changed his
limit to $3 per day until he had $2 left. Then, he used the last $2 on the final day.
6. Seconds 5 10 15 16 20 21 30 31 50
Jump Rope Jumps 15 30 45 49 65 70 115 118 175
7. Kara is a triathlete. It took her 15 minutes to swim, 80 minutes to bike, and 40 minutes to run
one race.
1.5 km 40 km 10 km
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Lesson 12.5 Skills Practice page 4
8. Days 0 5 10 17 18 20 21
Calling Card Minutes 100 70 40 40 30 10 0
Graph each piecewise function from the table or context.
9. Minutes 0 1 10 20 40 41 50
Gallons of Water in Tub 0 2 20 40 40 36 0
Variable Quantity Upper Bound Lower Bound Interval
Minutes (x) 50 0 5
Galons of Water in Tub f(x) 50 0 5
x2015
5
Gal
lons
of W
ater
in T
ub
Minutes
10
15
20
25 30 35 40 45 501050
y
25
30
35
40
45
50
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Name ________________________________________________________ Date _________________________
10. At 10:00, Sheila biked to Jill’s house. She stayed at Jill’s for an hour. Then, she biked back home.
Sheila can bike 10 miles per hour uphill and 20 miles per hour downhill. (Hint: Use minutes as the
x-value.)
Sheila’s house
10 Miles
Jill’s house
Variable Quantity Upper Bound Lower Bound Interval
Minutes (x) 150 0 15
Distance from Home f(x) 10 0 1
x
y
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Lesson 12.5 Skills Practice page 6
11. Kyle saved $4 a day for 30 days. Then, he spent $5 a day for 8 days. After that, he started saving
again at a rate of $3 a day for 22 days.
Variable Quantity Upper Bound Lower Bound Interval
Days (x) 60 0 10
Money f(x) 150 0 25
x
y
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Name ________________________________________________________ Date _________________________
12. Hours 0 2 5 6 7 8 10
Miles Driven 0 140 350 395 460 525 655
Variable Quantity Upper Bound Lower Bound Interval
Hours (x) 10 0 1
Miles f(x) 700 0 100
x
y
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Lesson 12.5 Skills Practice page 8
13. Miles received a $50 gift card to an online music store from his aunt. He decided to spend a
certain amount each day to extend his enjoyment of the gift card. For the first three days, he set
his limit for $5 a day. Then, he was worried it wouldn’t last long enough at that rate, so he changed
his limit to $3 a day until he had $2 left. Then he used the last $2 on the last day.
Variable Quantity Upper Bound Lower Bound Interval
Days (x) 20 0 3
Money f(x) 50 0 5
x
y
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Name ________________________________________________________ Date _________________________
14. Seconds 5 10 15 16 20 21 30 31 50
Jump Rope Jumps 15 30 45 49 65 70 115 118 175
Variable Quantity Upper Bound Lower Bound Interval
Seconds (x) 50 0 5
Jumps f(x) 250 0 25
x
y
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Lesson 12.5 Skills Practice page 10
15. Kara is a triathlete. It took her 15 minutes to swim, 80 minutes to bike, and 40 minutes to
run one race.
1.5 km 40 km 10 km
Variable Quantity Upper Bound Lower Bound Interval
Minutes (x) 200 0 20
Kilometers f(x) 55 0 5
x
y
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Name ________________________________________________________ Date _________________________
16. Days 0 5 10 17 18 20 21
Calling Card Minutes 100 70 40 40 30 10 0
Variable Quantity Upper Bound Lower Bound Interval
Days (x) 21 0 5
Minutes f(x) 100 0 10
x
y
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