What is a?

45 = 4 (a + 3) - 3

A: a = - 9

B: a = 12

C: a = 9

D: a = - 12

First, you need to distribute 4 throughout the parenthesis.

You get 45 = 4a + 12 - 3

Put 12 and 3 together.

45 = 4a + 9

Subtract 9 from both sides.

36 = 4a

Divide each side by 4 and you have your answer.

45 = 4 (a+3) - 3

45+3 = 4 (a+3)

48 = 4 (a+3)

48/4 = a+3

12 = a+3

a = 9