operations on functions: find f(g(5)) and g(f(5))

[Jen123]

Given that f(x) = 3x and g(x) = 4x - 3, find f[g(5)] and g[f(5)].

I'm not sure where to begin on this problem, so can someone coach me through this please? Thank you!

 

[skeeter]

f(x) = 3x
f(5) = 3(5) = 15

g(x) = 4x - 3
g(5) = 4(5) - 3 = 17

f[g(5)] = f(17) = 3(17) = 51

g[f(5)] = g(15) = 4(15) - 3 = 57


kapish?