Functions help (pre-calc)?

Question

let f(x) = x+9 and g(x) = x^2 -16

find f(g(6)) and g(f(6))

Any help would be appreciated. I'm not looking for just answers, but explanations so that I understand it and can do similar problems. Thanks so much and 10 points to the best answer.

Answer 1

f(g(6)) means put 6 in for the x in g(x) and see what that is, then put that answer in for the x in f(x) and see what that comes out.

The other just does in in the opposite order.