to find the rate of change would mean finding the slope or the gradient between the two points, and the equation for that is y2-y1/x2-x1
so your points are (2,2) and (6,14)
so your y2 is 14, your y1 is 2 , x2 is 6 and x1 is 2
so substitute into the formula :
14-2 / 6-2 = 12/4 = 3
