Question 382389
Given:
h(t)=-16t^2+368t
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You can set h(t) to zero and solve for t:
h(t)=-16t^2+368t
0=-16t^2+368t
0=16t^2-368t
0=16t(t-23)
t = {0, 23}
answer: 23 seconds
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OR, you can think of like:
The vertex is at it's highest point AND at mid-flight.  If we found time (t) when it reaches the vertex, we simply double it for the answer.
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time (t) at vertex:
t = -b/(2a) = -368/(2*(-16)) = -368/(-32) = 11.5 sec
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Answer:
2*11.5 = 23 seconds
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