SOLUTION: Janet threw a basketball. The equation h(t)= -16t^2 +5t+5 describes the height h of the ball in t seconds after she threw it. How many seconds passed before the ball hit the grou

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Question 676747: Janet threw a basketball. The equation h(t)= -16t^2 +5t+5 describes the height h of the ball in t seconds after she threw it.
How many seconds passed before the ball hit the ground?
How long did it take for the ball to reach its maximum height?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi

h(t)= -16t^2 +5t+5 

h(t)=  -16(x- 5/32)^2 + 25/64 + 5

h(t)=  -16(x- 5/32)^2 + 5.3906  ||Parabola opening Downward  V(5/32, 5.3906)

How long did it take for the ball to reach its maximum height?  5/32 sec

How many seconds passed before the ball hit the ground? h(t) = 0

 -16t^2 +5t+5 = 0

t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+

t+=+%28-5+%2B-+sqrt%28+345%29%29%2F%28-32%29+

          t = .7381 sec passed before the ball hit the ground