Question

A man standing on the edge of a 30 foot tall building throws a ball at a velocity of 25 ft/sec into the air. The function of the ball's height, h (in feet), at t seconds is given. h(t) = -5t² + 25t + 30. How long does it take for the ball to hit the ground? _________ seconds. * 1 point

Answer 1

6 sec

Explanation:

when the ball hits the ground h(t) = 0

Factor:

-5(t² - 5t - 6) = 0

-5(t - 6)(t + 1) = 0

solutions for t: 6, -1

Therefore, it takes 6 seconds for the ball to hit the ground after being thrown from a 30 ft tall building