Question 236695
If an object is propelled upward from ground level with an initial velocity of 224 feet per second, its height h in feet t seconds later is given by the equation h = 224t - 16t2. After how many seconds does the object hit the ground?
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It hits the ground when its height is zero.
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Solve -16t^2 + 222t = 0
Factor:
-2t(8t- 111) = 0
t = 0 means the object was on the ground at time zero.
t = 111/8 = 13.875 sec. is the time when the object is on the ground again.
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Cheers,
Stan H.