Question 302185
h = 48t - 16t2
Set h = 20 and solve for t
20 = 48t - 16t2
-16t^2 + 48t - 20 = 0
*[invoke solve_quadratic_equation -16,48,-20]

t = x-axis, h = y-axis
It's a 20 ft going up, then again coming down.