When
the ball is in the ground, its height is basically equal to zero thus making
our equation,
<span> -16t^2 + 272t + 1344 = 0</span>
Simplifying
the equation will give us,
<span> - t^2 + 17t + 84 = 0 or t^2 – 17t – 84 = 0</span>
Factoring
out the equation will give us,
<span> (t – 21)(t + 4) = 0</span>
Thus,
t = 21 or t = -4. -4 is an extraneous root. Thus, the answer is t = 21.
<span>Answer:
21 seconds</span>
