<PRE><B>Question 340284</B>
Given:
h = 224t - 16t^2
where
h is height in feet
t is time in seconds
.
To determine when the object hit the ground,
set h to zero (because zero is when the object is on the ground) and solve for t:
h = 224t - 16t^2
0 = 224t - 16t^2
0 = 14t - t^2
factoring the right side:
0 = t(14 - t)
setting each term on the right to zero we get:
t = {0, 14}
.
t=0 is when the object just started its flight
So,
t = 14 seconds (solution)

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