Question

If f(x)=4x-8, what is f^-1(x)

Answer 1

x = 4x - 8
let's replace x with y.
y = 4x - 8
y + 8 = 4x
x = y/4 + 8/4
x = y/4 + 2
and now replace y with x.
so x = x/4 + 2
and inverse f^-1
f^-1 (x) = x/4 + 2