Question

A ball is thrown vertically upward from the top of the building 96 feet tall with an initial velocity of 80 feet per second. The distance s (in feet) of the ball from the ground after t seconds is s=96+80t-16tsquared. After how many seconds does the ball strike the ground?

Answer 1

Explanation:

When the ball hits the ground , the height = 0

0 = 96 + 80 t - 16t^2

Use Quadratic Formula with a = -16 b = 80 c = 96

to find t= 6 seconds