Given f(x) = 2x + 9, if f(x) = 15, find x.

If f(x) = 15, then rewrite the equation replacing the f(x) with 15

15 = 2x + 9

subtract 9 from sides

15 - 9 = 6

9 - 9 = 0

then, you would be left with 6 = 2x

divide by 2 on both sides

6/2 = 3
2x/2 = x

x would be 3 :)

5(2a-5+b). xbox xboxxbx xb

The question is kind of confusing. if it's asking how many variations of answers can you give. then do 4^5 for your answer.this would be something like the first question could be a and the 2nd c or first b next c etc. if you can, ask the teacher for a better confirmation of what it's asking. if i'm assuming correctly what it's asking, it's 625 different variations.