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if an object is dropped from a height of 144 ft the function h t equals negative 16 t squared + 144 gives the height of the object after T seconds when will the object hit the ground

User Vivek Sadh
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1 Answer

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18 votes

Given data:

The expression for the height of the object is h= -16t^2 +144.

When the object hits the ground its height becomes zero.


\begin{gathered} h=0 \\ -16t^2+144=0 \\ -16t^2=-144 \\ t^2=9 \\ t=3,\text{ -3} \\ t=3\text{ s} \end{gathered}

Consider only positive value of time.

Thus, after 3 second object hit the ground.

User Leah
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