Here's the question you clicked on:
aelit
lim x approaches -1 (x^2-4x) / (x^2-3x-4)
have you tried factoring both top and bottom to see if anything cancels? you should do this if you have 0/0 do you have 0/0 when you evaluate the function at x=-1?
you could still factor of course top and bottom (and cancel any common factors on top and bottom) even if you don't have 0/0 to get better idea of what the graph looks like
The point is that is where I would start. Factoring.