SOLUTION: The height of an object thrown upward from the floor of a canyon 106 feet deep with an initial velocity of 120 feet/second is given by the equation: h=-16t2 + 120t - 106 How lo

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: The height of an object thrown upward from the floor of a canyon 106 feet deep with an initial velocity of 120 feet/second is given by the equation: h=-16t2 + 120t - 106 How lo      Log On


   

Question 466050: The height of an object thrown upward from the floor of a canyon 106 feet deep with an initial velocity of 120 feet/second is given by the equation:
h=-16t2 + 120t - 106
How long will it take the object to rise to the height of the canyon wall? Round answer to the nearest hundreth.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The height of an object thrown upward from the floor of a canyon 106 feet deep with an initial velocity of 120 feet/second is given by the equation:
h=-16t2 + 120t - 106
How long will it take the object to rise to the height of the canyon wall? Round answer to the nearest hundreth.
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solve -16t^2+120t - 106 = 106
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-16t^2 + 120t -212 = 0
Divide thru by -4 to get:
4t^2 - 30t + 53 = 0
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t = -b/(2a)
t = -120/(2*-16) = 3.75 seconds
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Cheers,
Stan H.
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