SOLUTION: The height h of a rock t seconds after it is dropped off a cliff is given by the equation h=-16t^2 + 400. How many seconds after the Rock is dropped will it hit the ground?
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-> SOLUTION: The height h of a rock t seconds after it is dropped off a cliff is given by the equation h=-16t^2 + 400. How many seconds after the Rock is dropped will it hit the ground?
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Question 1045242: The height h of a rock t seconds after it is dropped off a cliff is given by the equation h=-16t^2 + 400. How many seconds after the Rock is dropped will it hit the ground? Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! The ground is 0 feet, so 0=-16t^2+400
-16t^2=-400, 16t^2=400
t^2=25, dividing both sides by 16
t=5 seconds.
