This is the concept of applications of polynomial equations. Given that the height of the ball is modeled by the function: h(t)=16t^2-64t the maximum height will be calculated as follows; h(t)=16t(t-4) therefore: t=0 or t=4 h(4)=-64(4)+16(4^2) =0
A linear equation would be the best fit, but the last point (-1,-7) kinda messes it up. If the -7 would have been a -6 the line y=-2x-8 would fit perfectly.