To solve any formula for a single variable, you must isolate the variable, either by multiplying, dividing, adding, or subtracting.

Example:

EX1: X+3=12 Solve for X

To get X on one side, you must reduce both sides by 3

X+3=12

   -3   -3

X=9

EX2: Division/Multiplication

3X=21

(divide both sides by 3)

3X 3

=

21 3

X=7

EX3: Combination

Multiply both sides by 2

3X+7=15

Reduce both sides by 7

3X=8

Then divide both sides by 3

X=8/3

Sample Problems:

1) Solve for x

3X-7 5

=15

2) Solve for n

4n+8y 2

=2

3) Solve for g

4g+6g+5 3

=6g+12