Solve ax−12=9

Question

A. x=−3a

B. x=3a

C. x=−21a

D. x=21a

Answer 1

To solve the equation ax - 12 = 9, we can first add 12 to both sides of the equation:
ax - 12 + 12 = 9 + 12
ax = 21

Next, we can divide both sides of the equation by a to solve for x:
(ax)/a = 21/a
x = 21/a

Therefore, the correct answer is D. x = 21a.