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Can you please help me solve this I have no clue what to do

Can you please help me solve this I have no clue what to do-example-1
User Jymbo
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1 Answer

3 votes

The equation thatmodels the movement of the objet is:


h(t)=16t^2+60t

where h(t) is equal to the hight and t is the time, so we can replace h(t)=36 so:


\begin{gathered} 36=16t^2+60t \\ -16t^2+60t-36=0 \end{gathered}

now we can use the cuadratic function to find the values of t so:


\begin{gathered} \frac{-b\pm\sqrt[]{b^2-4(a)(c)}}{2a} \\ a=-16 \\ b=60 \\ c=-36 \end{gathered}

So the equation become:


\frac{-60\pm\sqrt[]{60^2-4(-16)(-36)}}{2(-16)}

Now we operate so:


\begin{gathered} \frac{-60\pm\sqrt[]{3600-2304}}{-32} \\ \frac{-60\pm\sqrt[]{1296}}{-32} \\ (-60\pm36)/(-32) \end{gathered}

Now we solve bout solutions:


\begin{gathered} t_1=(-60+36)/(-32)=0.75 \\ t_2=(-60-36)/(-32)=3 \end{gathered}

So he will reach a hight of 36 feets at 0.75 seconds and a time of 3 seconds because the first time is when his is going up and the second time is we he is falling back to the grownd.

User Mridul Kashyap
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5.8k points