Question

Let f(x) =7x-13. Find f -1(x)

Answer 1

F(x) = 7x - 13
y = 7x - 13
7x - 13 = y
7x = y + 13
x = (y + 13)/7
f^-1(x) = (x + 13)/7

Answer 2

If you’re trying to find f(-1) it would be -20