Functions of Operations

Question

KEY

f(x)=2x+1

g(x)=3x+4

h(x)=3x^2

k(x)=x^2-4x

1) (h of f)(3)

looked up answer: 147

2) (g of f)(-4)

looked up answer: -17

I wanna know step by step please

Answer 1

h(f(x))=h(2x+1)=h(7)= 3(7^2)=3(49)= 147

f(3)=2(3)+1=6+1=7

g(f(x))=g(2x+1)=g(f(-4))=g(2(-4)+1)=g(-8+1)

= g(-7)=3(-7)+4=-21+4=-17

f(-4)=2(-4)+1=-8+1=-7