A hot air balloon is ascending straight up at a constant speed of 7.0 m/s. When the balloon is 12.0m above the ground, a gun fires a pellet straight up from the ground level with an initial speed of 30.0 m/s. Along the paths of the balloon and the pellet, there are two places where each of them has the same altitude at the same time. How far above the ground level are these places?(adsbygoogle = window.adsbygoogle || []).push({});

For this problem, I need to find two distances, so I tried to find the two times for the distances first but I can't work it out. This is what I have:

let v=velocity of balloon, t=time, V=velocity initial, a=acceleration

vt=Vt+0.5(-9.81)t^2

7t=30t+(-4.91)t^2

7t=30t-4.91t^2

0=23t-4.91t^2

then I factored it

0=t(23-4.91t)

t=0, 4.68 or 4.7

I'm missing one more time and distance or is this time also incorrect? I don't know how to solve this problem, plz help me out

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# Homework Help: More Free Fall!

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