SOLUTION: a preson standing close to the edge on the top of a building throws a baseball vertically upward. the equation describeshte ball's heigthabove the ground after t seconds.

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Question 211682: a preson standing close to the edge on the top of a building throws a baseball vertically upward. the equation describeshte ball's heigthabove the ground after t seconds. h=-16t^2+64t+160 a) how many seconds does it take until the ball finally hits the ground? round to tenths. b.) find t=0 and describe what this means.
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
a preson standing close to the edge on the top of a building throws a baseball vertically upward. the equation describeshte ball's height above the ground after t seconds. h=-16t^2+64t+160
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a) how many seconds does it take until the ball finally hits the ground? round to tenths.
-16t^2 + 64t + 160 = 0
t = [-64 +- sqrt(64^2-4*-16*160)]/-32
t = [-64 +- sqrt(14336)]/-32
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Positive solution:
t = (-64-119)/-32 = 5.74 seconds
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b.) find the height of the building by finding h(t=0) and describe what this means.
h(0) = 160 ft (height of the building)
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Cheers,
Stan H.