Question

f(x) = 3x + 12

Answer 1

a.
f(x)=y=3x+12
now
x=y/3 - 4
got it. after this
g(y)=x=y/3 -4
now replace x and y in g(y)
and its your answer
g(x)= x/3 -4

b.
i dont know what composite function is.

c.f(g(-2))
g(-2)= -2/3-4=-14/3
f(g(-2))= (-14/3)*3 +12=-2
domain is the whole empire of no. excluding complex lol.
(- infi, infi)

Answer 2

Thanks alot :D np about b :)