SOLUTION: A volleyball is thrown straight up. The equation that describes its motion is h(t) = -16t^2 + 48t + 4, where h represents the height in feet and t represents time in seconds. How

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Question 1077665: A volleyball is thrown straight up. The equation that describes its motion is h(t) = -16t^2 + 48t + 4, where h represents the height in feet and t represents time in seconds. How long will it take for the ball to hit the ground? Round to the nearest hundredth, if necessary.
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
h(t) = -16t^2 + 48t + 4
Let h(t)=0, and solve for the positive root
Divide by 4
-4t^2+12t+1=0 or 4t^2-12t-1=0
t=(1/8)(12+/- sqrt (144+16); sqrt 160=12.65
t=24.65/8=3.08 sec
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