Answer:
t = 96 seconds
Step-by-step explanation:
The ball will hit the ground at height 0 (the ground is a height of 0), so plug in 0 for h.
h = -16t^2 + 20t + 6
0 = -16t^2 + 20t + 6
Now all that's left is to solve. First simplify:
0 = -8t^2 + 10t + 3
Use the quadratic formula.
[tex]x = \frac{-b+-\sqrt{b^{2}-4ac} }{2a}[/tex]
[tex]t = \frac{-10+-\sqrt{10^{2}-4(-8)(3)} }{2(-8)}[/tex]
Simplify further to get t = -16 and t = 96.
Since time can't be negative in this case, the answer is t = 96 seconds!
