Question

What is the inverse of the function f(x) = 2x – 10?

Answer 1

h(x) = 2x + 5

Explanation:

I took the test

Answer 2

f(x) = 2x - 10

let y = f(x)

y = 2x - 10 solving for x.

y + 10 = 2x

2x = y + 10

x = (y + 10)/2

Recall f(x) = y. Implies x = f⁻¹(y)

x = (y + 10)/2

f⁻¹(y) = (y + 10)/2

So as well:

f⁻¹(x) = (x - 10)/2