1. The problem statement, all variables and given/known data On earth, a ball is launched over level ground. It's vertical equation of motion is y(t) = -4.9(t2 - 8t - 20) A) Find tymax and ymax B) Find vyinitial and vyfinal 2. Relevant equations y(t) = Yi + via + 1/2at2 Vf = vi + at 3. The attempt at a solution I tried to complete this problem by completing the square. I'm not sure I completed the square correctly. For the completed square I got: -4.9(t-4)2 + 58.4 making tymax = 4s and ymax = 58.4 m To get tymax I set the equation equal to zero and factored I got 0 = -4.9(t + 2) (t -10) making ti = -2 s and tf = 10 s For Vyi I took the derivative of the y(t) equation and plugged in ti Vyi = -9.8(-2) + 39.2 Vyi = 58.6 m/s For Vyf I used the derivative and plugged in tf Vyf = -9.8(10) + 39.2 Vyf = -58.8 m/s If I did not complete the square in the first part, please show me how to do it rather than telling me a different way to go about the problem. Thank you!!!