SOLUTION: please help me answer this question: a flare is launched from a life raft with an initial velocity of 80 meters per second. how many seconds will it take for the flare to return t

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Question 357043: please help me answer this question:
a flare is launched from a life raft with an initial velocity of 80 meters per second. how many seconds will it take for the flare to return the sea?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
a flare is launched from a life raft with an initial velocity of 80 meters per second. how many seconds will it take for the flare to return the sea?
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h(t) = -9.8t^2 + 80t
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When the flare is at sea level, it height is zero.
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Solve -9.8t^2+80t = 0
t(-9.8t+80) = 0
t= 0 when the flare leaves the raft.
-9.8t+80 = 0 when the flare hits the water.
9.8t = 80
t = 8.16 seconds
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Cheers,
Stan H.