<PRE><B>Question 384795</B>
 A ball is thrown straight up into the air. The approximate height h of the ball after t seconds can be appromimately modeled by the function 
h(t) =-16t^2+55t. What is the maximum height that the ball reaches? 
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Max occurs when t = -b/(2a) = -55/(2*-16) = 55/32
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Height at that time = h(55/32) = 47.27 ft.
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Cheers,
Stan H. 
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