SOLUTION: The height h in feet of an object after t seconds is given by the function h=-16t^2+60t+9.... How long will it take the object to hit the ground? Round your answer to the nearest

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Question 86274: The height h in feet of an object after t seconds is given by the function h=-16t^2+60t+9....
How long will it take the object to hit the ground? Round your answer to the nearest thousandth....
Answer by stanbon(48546) About Me  (Show Source):
You can put this solution on YOUR website!
The height h in feet of an object after t seconds is given by the function
h=-16t^2+60t+9....
How long will it take the object to hit the ground? Round your answer to the nearest thousandth....
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When it hits the ground its height is zero.
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-16t^2+60t+9 = 0
t = [-60+-sqrt(60^2-4*-16*9)]/-32
t = [-60+-sqrt(4176)]/-32
Find the positive answer:
t = 3.8944 seconds
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Cheers,
Stan H.