How to do functions?

Question

What is the value of g[f(3)] for the functions f(x) = 3x – 5 and g(x) = x 1?

What is the value of f(6) for the function f(x) = 3x – 5?

Answer 1

for the first problem plug 3 to every x in the function f(x), then with that answer, you plug it into every x of g(x).

the second problem you just plug in 6 to x in f(x)  

Answer 2

plug the numbers into the equations where you see the X:  f(6) looks like this: 3(6)-5 f(x)=13