Find and simplify 4f (x) = x^2/x-9

We have:

4f (x) = x^2 / (x-9)

To get f (x), we will simply divide both sides by 4:

f (x) = [x^2 / (x-9) ] / 4

This gives f (x) in the simplest form as follows:

f (x) = 4x^2 / x-9