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.
