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2 years ago

12

An object is dropped from a height of 400 feet. The amount of time, in seconds, the object takes to hit the ground can be found

by solving the equation -16t^2+400=0 . How many seconds will it take to hit the ground?

1 answer:

lidiya [134]2 years ago

6 0

-16t^2+400=0

16t^2=400

take square root on both sides.

$\sqrt{16t^2} =\sqrt{400}$

4t=20

t=20/4

t=5

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