If Y=(X) has a range of [3,18], what is the range of Y =1/3f(x-2)-4?

I took the first 3-4=-1
Then the 18-4=14
R[-1,14]
But I got it wrong so can you please explain the steps

maybe you mean:

If y = f (x) has a range of [3,18], what is the range of y =(1/3)f(x-2)-4?
min of f(x-2) is 3 where y = (1/3)(3) - 4 = -3
max of f(x-2) is 18 where y = (1/3)(18) - 4 = 2
so I think the range goes from -3 to +2