Question

After how many seconds is the height 68 feet? When the equation is h=-16t2+64t+8

Answer 1

68=-16t2+64t+8
16t2-64t+60=0

4t2-16t+15=0
(2t-5)(2t-3)=0
t=5/2 or 3/2
The object is at 68 feet after 3/2 secs, and returns to 68 feet after another second..