Question

Which of the following is an example of a valid use of the addition property of equality?

A.
to isolate the g in the equation g – 4 = 0, add 4 to both sides of the equation
B.
to isolate the g in the equation g – 4 = 0, subtract 4 from both sides of the equation
C.
to isolate the g in the equation –4g = 0, add 4 to both sides of the equation
D.
to isolate the g in the equation –4g = 0, subtract 4 from both sides of the equation

Answer 1

A.
to isolate the g in the equation g – 4 = 0, add 4 to both sides of the equation

On any equation, you can do anything to it as long as you do it to both sides.  If you add 4 to both sides the 4 gets cancelled out on the left side g-4+4=0+4 so you are left with g=4