Question 1160555
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The maximum height is at the vertex of the parabola described by the quadratic function.


The vertex of *[tex \LARGE \rho(x)\ =\ ax^2\ +\ bx\ +\ c]


is at *[tex \LARGE \(\frac{-b}{2a},\,\rho\(\frac{-b}{2a}\)\)].  For your height function, the maximum height is the *[tex \Large y]-coordinate of the vertex point.


The height of the ball when it hits the ground is zero feet.  Solve:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ -16t^2\ +\ 72t\ +\ 40\ =\ 0]


for the positive root.
								
								
John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
<img src="http://c0rk.blogs.com/gr0undzer0/darwin-fish.jpg">
*[tex \Large \ \
*[tex \LARGE \ \ \ \ \ \ \ \ \ \  
								
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