The Algebra Teacher\'s Guide to Reteaching Essential Concepts and Skills

Name Date

WORKSHEET 3.3: SOLVING EQUATIONS BY MULTIPLYING OR

DIVIDING

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Follow the steps below to solve an equation by multiplying or dividing:

1. Isolate the variable on one side of the equation by multiplying or dividing both sides of
   the equation by the same nonzero number.


2. Find the value of the variable.

EXAMPLES

Solve each equation.

7 x=− 28 Divide each side by 7.

7 x

7

=

− 28

7

;x=− 4

−

3

4

x= 15 Multiply each side by−

4

3

. −

4

3

(

−

3

4

x

)

=−

4

3

×

15

1

;x=− 20

DIRECTIONS: Write the number you would use to multiply or divide both sides of the

equation. Then solve the equation.

1. 6 a=− 42 2.
   x
   9
   =− 18 3. −

1

3

x= 12

4. 24 y=− 8 5. −n= 100 6. 15 =

1

3

d

7. −

3

5

x=− 60 8. 24 =−

a

2

9. 
   

   26 =− 13 x

   
   


10. 
    

y

6

= 12 11.

3

4

x= 24 12. − 20 =− 2 y

CHALLENGE:Martin solved the equation− 2 x=20 by dividing both sides of

the equation by−2. Brianna solved the equation by multiplying both sides

by−

1

2

. Who is correct? Explain your answer.

93

Copyright

©

2011 by Judith A. Muschla, Gary Robert Muschla, and Erin Muschla. All rights reserved.