SOLUTION: If an object is thrown upward with an initial velocity of 80 ft/sec, its height after t sec is given by h = 80t - 16t2 Find the number of seconds before the object hits the ground.

Question 240303: If an object is thrown upward with an initial velocity of 80 ft/sec, its height after t sec is given by h = 80t - 16t2 Find the number of seconds before the object hits the ground.
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
If an object is thrown upward with an initial velocity of 80 ft/sec, its height after t sec is given by h = 80t - 16t2 Find the number of seconds before the object hits the ground.
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That's the time that h = 0. There are 2 of them, one at t = 0, and the other when the object returns to the ground.
80t - 16t^2 = 0
16t^2 = 80t
t = 0
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16t = 80
t = 5 seconds
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