Question

Matthew dropped a tennis ball off the roof of 100 foot tall building. The objects height (y) is modeled by the equation below. At what time (t) does the ball hit the ground? Round your answer to the nearest tenth

Answer 1

2 seconds later

Explanation:

Since the required equation is lacking, let the equation modeled by the height be expressed as y = -16t² + 64

The ball hits the ground at y =0. Substitute y = 0 into the expression and find t;

Since y = -16t² + 64

0 = -16t² + 64

16t² = 64

t² = 64/16

t² = 4

t = ±√4

t = 2 and -2

Time cannot be negative, hence the ball hits the ground 2 seconds later.

Note that the equation used was assumed. Similar solution can be applied for any given equation.