Question

Find x if f(x) = 2x + 7 and f(x) = -1.


-4
-3
5

Answer 1

They're giving you the result of this function, -1, and you need to find x. So we're going to set -1 equal to the function of x:
-1=2x+7
From here, you need to solve this for x by getting x by itself on one side of the equation.

Answer 2

Precisely. I couldn't have said it better myself :)

Answer 3

ok