Solving Fraction Equations by

MultiplyingLesson 5-5

If the variable is in the fraction…

• When the variable is the numerator of the fraction, then it suggests a division problem.

• To solve a division problem, the inverse operation is multiplying.

Example

y

8= 20

This equation reads “y divided by 8 equals 20.”

The opposite of dividing by 8 is multiplying by 8.

Multiply both sides by 8.

y

8= 208

1·

11

y1

=

·8

160

y =160

Example 2

m2

= 3·21

11

m1 =

· 2

6

m =6

Check answers in the original equation.

m2 =362 =3

3 =3

If the variable is being multiplied by a fraction…

• To isolate a variable that is being multiplied by a fraction, multiply by the reciprocal.

• Perform the same operation on the other side of the equation.

Example

23

r = 10·32

1111

1r =

· 321

5

1151

r = 15

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