h=80t-16t^2

Question

h=height in feet

t=time in seconds

if h=96 feet, t=?

Answer 1

h = 80t - 16t²

 

96 = 80t - 16t²

 

0 = -16t² + 80t - 96

0 = t² - 5t + 6

(divided both sides by -16)

0 = (t-2)(t-3)

 

t = 2 sec and 3 sec

 

The projectile passes through 96 feet a t=2 sec on the way up and again at t=3 sec on the way back down.