Question

if f(x)=x^2-5 and g(x)=6x then g(f(x)) is equal to

Answer 1

g(x) = 6x 

g(f(x)) 
= 6((x^2) - 5) 
= (6x^2) - 30 

so its equal to
(6x^2) - 30

Answer 2

Plug f(x) as x in g(x) and you get 6(x^2-5), which is g(f(x)) = 6x^2-30.