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

Diff. Quotient : ( f(3+h) - f(3) ) / h

b) f(x) = (x+8) / (x+6)

Diff. Quotient : ( f(x) - f(6) ) / x-6

I understand how to do the problem, but for some reason I just can't get the right answer. I have come up with four different ones. Can someone do the math here for me? I can't see what I am doing wrong. If I have to, I'll post my work.