Question 766437
The Height of a projectile above the ground is described by the function P(t)=-16t^2+640t

-When will the projectile get back to the ground, height = 0?
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P(t)=-16t^2+640t = 0
Solve for t.
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-When will the projectile be 3696 feet above ground?
P(t)=-16t^2+640t = 3696
Solve for t (might be 2 values, 1 going up, 1 coming down)