Find a formula for the inverse of the following.

Question

f(x) = ax + b,  a ≠ 0

Answer 1

y = ax + b

y - b = ax

x = (y-b)/a

the inverse function, upon swapping x and y is:

y = (x-b)/a

CHECK:

a[(x-b)/a ] + b = x

((ax+b)-b)/a = x