For y = (x^2 -4)/((x +2)(x^2 -49)) the numerator factors to (x -2)(x +2), so the factor of (x +2) will cancel with that in the denominator, leaving y = (x -2)/(x^2 -49)
There are points of discontinuity at the hole, x=-2, and at each of the vertical asymptotes, at x=-7, +7. The horizontal asymptote is y=0.