Question

Let f(x) = –4x + 7 and g(x) = 10x – 6, find f(g(x)).

Answer 1

The idea is to start with f(x) = –4x + 7 and replace each 'x' with 'g(x)'

So

f(x) = –4x + 7

becomes

f(g(x)) = –4(g(x)) + 7


Then replace the "g(x)" on the right side with "10x-6" to get


f(g(x)) = –4(10x-6) + 7


From here, simplify.