Question

Sharon kicks a ball from the ground into the air with an upward velocity of 64 feet per second. The function h = -16t2 + 64t models the height h, in feet, of the ball at time t, in seconds. When will the ball reach the ground again?

Answer 1

Explanation:

h = 64t - 16t².

When the ball reaches the ground, h = 0.

Therefore 64t - 16t² = 0, 16t(4 - t) = 0, t = 0 or t = 4.

Therefore the ball reaches the ground 'again' at t = 4.

Answer 2

t=4 thank me later :)