Question 812240
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In the first place, *[tex \Large h\ =\ -16t^2\ +\ 64\ +\ 260] is NOT a quadratic equation.  It is a quadratic function.  There is a difference and it is important.


In the second place, your quadratic function, given that it is supposed to model the height of a projectile near the surface of Earth, is incorrect.  It needs to be *[tex \Large h\ =\ -16t^2\ +\ 64t\ +\ 260].


Presuming that the 260 ft height of the building is measured from the ground, the ground must then be at height zero, right?  So set your function equal to zero (thereby creating a quadratic <i>equation</i>) and solve for *[tex \Large t]


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ -16t^2\ +\ 64t\ +\ 260\ =\ 0]


Solve for *[tex \Large t].  Discard the negative root since you don't care what went on <i>before</i> the object was thrown (do you?). 


John
*[tex \LARGE e^{i\pi}\ +\ 1\ =\ 0]
My calculator said it, I believe it, that settles it
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