The equation h = -16t^2 + 32t + 9 gives the height of a ball, h, in feet above the ground, at t seconds after the ball is thrown upward. How many seconds after the ball is thrown will it reach its maximum height? What is its maximum height?

Answer 1

find the vertex of the parabola.
The t of the vertex tells you when it reached the maximum height, the h tells you what that height is.