tolong bantu pakai caranya ....

f(3x+5) = 7 - 3x. f(-4) = ...

3x+5 = -4
3x = -5 -4
3x = -9
x = -3
masukkan x kedalam fungsi

f(3(-3)+5) = 7 - 3(-3)
f(-4) = 7 + 9
f(-4) = 17
Semoga membantu ^_^