My last one, can some plz helps me ​

Afunction is given: f(x)=3x+12 a. determine the inverse of this function and name it g(x) b. use composite functions to show that these functions are inverses. c. f(g(– explain: what is the domain?

If f(x)=-x^2+6x-1 and g(x)=3x^2-4x-1,find(f+g)(x)

In a column proof the right column states your reasons