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A rocket is launched from a tower. The height of the rocket, y in feet, is related to the time after launch, x in seconds, by the given equation. Using this equation, find the time that the rocket will hit the ground, to the nearest 100th of second. y = –162+ 248x + 116a rocket is launched from a tower. The height of the rocket, y in feet, us related to the time after launch, x in seconds, by given equation. Using this equation,find the time that the rocket will hit the ground, ro the the nearest 100th of second y= -16x^2+248x+116

User Ibm
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1 Answer

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When rocket hit the ground the height of rocket from the ground is 0. So y = 0, when rocket hit the ground.

Simplify the equation -16x^2+248x+116 = 0 by using quadratic formula to obtain the value ot time, x.


\begin{gathered} x=\frac{-248\pm\sqrt[]{(248)^2-4\cdot(-16)\cdot(116)}}{2\cdot(-16)} \\ =\frac{-248\pm\sqrt[]{68928}}{-32} \\ =(-248\pm262.54)/(-32) \\ =(-248-262.54)/(-32) \\ =-(510.54)/(-32) \\ =15.95 \end{gathered}

The negative value of time is neglected as time can never be negative.

Thus time at which rocket hit the ground is 15.95 seconds.

User Snuggs
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