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PLEASE SHOW WORK!!!!!!!!!

PLEASE SHOW WORK!!!!!!!!!-example-1

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Answer:

Explanation:

If h is the height of the ball off the ground, if we want to find the time, t, when the ball hits the ground again, we set h equal to 0, because the height of something when it is on the ground is 0.


0=-t^2+4t and solve for the values of t. Begin by factoring out a -t:


0=-t(t-4)

By the Zero Product Property, either -t = 0 or t - 4 = 0. We already know that at time 0 the ball hit the ground for the first time because that was given in the problem. That means that the ball hit the ground for the second time 4 seconds later.

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