So, using the fact that one x intercept is 7, and the vertex is (-2,-4), we can solve for the other x intercept. While there are many ways to solve this, the way I prefer to do it is to realize that the x intercepts are the same distance away from the vertex. this means that if the vertex is at x = -2, and one x intercept is at x = 7, the other will be at -11, as 7+2 = -2+11.
