Question

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

Answer 1

If h(x) is the inverse of f(x), then by definition of inverse function, we have

f(h(x)) = x

By definition of f(x), composing f with h gives

f(h(x)) = 2 h(x) - 10

Solve for h(x) :

x = 2 h(x) - 10

2 h(x) = x + 10

h(x) = (x + 10)/2

h(x) = x/2 + 5

So... whichever option most closely resembles this is the correct one. It's hard to tell exactly which one that would be.