Vertical asymptotes occur when the function is undefined. In the case of rational functions, this is where the denominator is zero.

In the special case that the numerator is zero at the same point, due to the same factor, you get a hole. for example, in your first function, you have a vertical asymptote at x = 0 (the denominator is zero when x = 0, but not the numerator), but a hole at x = -5 (since both the denominator and the numerator are zero there, you can factor the top and bottom in such a way as to "cancel" the bad factor).