Solving Equations Using Multiplication and Division

Algebra 1 Section 3.2a

A. Review1. To solve an equation, you try to isolate the

variable.2. Addition and subtraction are inverse operations

that can be used to isolate a variable.

B. Multiplication and Division are also Inverse Operations1. They can be used to isolate a variable by

a. Multiplying each side by the same number (to get rid of division)

Example: = 2

b. Dividing each side by the same number (to get rid of

multiplication)Example: 5x = 25

c. Multiplying each side by the reciprocal ( do get rid of a

fraction)Example: 12 = x

X4

-2 3

Problems:1. = 8

2. a = -10

3. -3x = 5

X4

56

4. x =

5. 30b = 5

6. =

57

17

-3 4

m-4

7. z = -5

8. t = |-15|

9. -6y = -|27|

34

12

34