-3f(x-4)=x^2

i have no clue what to do with the -3 in front of the f. please explain step by step as to how to do this question
the answer in the back is
-3x^2+24x-48

The problem probably said:

if f(x) = x^2 , find -3f(x-4)

f(x) = x^2
f(x-4) = (x-4)^2 = x^2 - 8x + 16
then -3f(x-4) = 3(x^2 - 8x + 16)
= -3x^2 + 24x - 48