Question 206880
First off, you need to realize that the x-coordinate of the vertex is the value of 'h'. So in this case, {{{h=-2}}} (you have the correct x-coordinate of the vertex). 



So all you need to do is plug in values that fall to the left and to the right of the x-coordinate of the vertex 'h'. So why not try plugging in x=0 (an easy value that is to the right of 'h'), x=-1, x=-3 (now we're to the left of 'h') and x=-4. Let me know how this goes.