SOLUTION: Velocity problem help! A rocket is fired upward at an initial velocity of 1008 ft/s from a tower that is 120 ft height. When will the rocket reach a height of 3896 ft above ground

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Question 256216: Velocity problem help!
A rocket is fired upward at an initial velocity of 1008 ft/s from a tower that is 120 ft height. When will the rocket reach a height of 3896 ft above ground level?
H=vt-16t^2.
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
A general formula for height is
(i) h%28t%29+=+-gt%5E2+%2B+V0t+%2B+S0
using given information, we get
(ii) 3896+=+-32t%5E2+%2B+1008t+%2B+120
setting (ii) = 0, we get
(iii) 0+=+32t%5E2+-+1008t+%2B+3776
Solving for t using the quadratic, we get
t ~ 4.346 seconds
or
t ~ 27.154 seconds