Question

write a formula for f of g of h, where f(x) = x-2, g(x)=-4x, and h(x)=4-x

Answer 1

Is it f(g(h(x))? Then, first, find a formula for g(h(x)). Sub h in g for x to get:
g(h(x)) = -4(4-x)
Then sub this in f(x) to get:
f(g(h(x)) = -4(4-x) - 2
You can simplify it now

Answer 2

f(g(h(x)))=f(g(4-x))=f(-4(4-x))=f(-16+4x)=(-16+4x)-2=4x-18. When you write f(x)=y, this means that f maps x to y. In this case, x is replaced by some other function.