Warm UpEvaluate each algebraic expression for the given value of the variables.

1. if

2. if

3. if

4. if

1.3 Solving EquationsAlthough they are closely related, a Great Dane weighs about 40 times as much as a Chihuahua.

When solving real-world problems, you will need to translate words, into algebraic expressions.

TranslateIn order to translate a word phrase into an algebraic expression, we must first know some key word phrases for the basic operations.

TranslateAddition Subtraction

Multiplication Division

Addition Examples

1. 3 more than

2. The sum of 10 and a number

3. A number increased by 4.5

Subtraction Examples

1. A number decreased by 4.2. The difference between 10 and

a number.

3. 6 less than a number .

Multiplication…

Multiplication expressions should be written in side-by-side form, with the number always first.

Multiplication Examples1. The product of 3 and a number .2. Twice a number.

3. 3.7 times a number .

Division

Division expressions should be written using the fraction bar instead of the tradition division sign.

Division Examples

1. The quotient of 25 and a number .

2. A number divided by 2.

3. 2.5 divides .

Combination ExamplesWrite an algebraic expression to represent each expression.

1. 2 more than 4 times a number.

2. The quotient of 5 less than the number and 12.

3. The square of a number decreased by the product of 5 and the number.

You Try!Write an algebraic expression to represent each expression.

1. 7 less than a number

2. The square of a number increased by 4 times the same number

3. Three times the difference of a number and 8.

You Try!Write an algebraic expression to represent each expression.

1. The product of 12 and the sum of negative 3 and a number

2. divided by 5

3. The quotient of and 4 added to 8.

Real Life• the area of a room with a length of 10

and a width of w

• the cost for tickets if you purchase 5 adult tickets at x dollars each

• the total cost for 5 adult tickets at x dollars each and 3 children’s tickets at y dollars each

Solving EquationsThe goal is to get the variable by itself by doing the opposite!

Whatever you do to one side of the you’ve got to do to the other side!

Keep it balanced!

ExamplesSolve each equation.

1.

2.

3.

ExamplesSolve each equation.

1.

2.

3.

4.

You Try!Solve each equation.

1.

You Try!Solve each equation.

1.

2.

HomeworkLesson 1.3Pgs. 22 #’s 9-18, 22-25