For fx=6x-5 and gx=3x^2-4 find the following (fog)(x)

Question

Having problems understanding
(gof(x)=g(f(x))= 3(f(x))^2-4
3(6x-5)^2-4
(36x-9-25)-4

Answer 1

f = 3(6x-5)^2 -4
= 3 (36 x^2 -60 x +25) - 4
= 108 x^2 -180 x +71

Answer 2

given two consecutive integers. The sum of three times the first integer and four times the second integer is 95. Find the integers