Question

A glass-enclosed elevator at a sports arena moves upward from the ground floor at a constant speed of h = 9t.

At the same time the elevator starts to rise, a cannon on the arena floor shoots a souvenir mini-basketball into
the air at an initial velocity of 60 feet per second. The height of the mini-basketball (neglecting air resistance)
can be modeled by the equation h=-16t' + 60t. In both equations, h is height in feet and t is time in seconds.
Find the time for the ball and the elevator to be at the same height again. If necessary, round your answer to
the nearest tenth of a second.
a. 1.7 seconds
c. 2.4 seconds
b. 3.2 seconds
d. 1.5 seconds​

Answer 1

1.7 3.2 SECOND

IF BALL SPIN INTO THE PERIMETER

Answer 2

b. 3.2 seconds

Explanation:

Given the 2 functions:

h = 9t

h= -16t² + 60t

When the height is the same for both objects:

9t = -16t² + 60t

0 = -16t² + 60t - 9t

0 = -16t² + 51t

0 = t(-16t + 51)

which has two solutions:

t = 0

or

-16t + 51 = 0

51 = 16t

t = 51/16 = 3.2