We can use the formula y2-y1/x2-x1 to find the answer. Therefore, we would have: 6-(-6)/-2-x equalling -3. So, 12/-2-x = -3. We multiply both sides by -2-x and get 12 = -3(-2 - x), then 12 = 6+ 3x. We then get 6 = 3x, and by dividing both sides by 2 we get x = 2.