SOLUTION: use 4.9t^2 + vot = s a coin is tossed downward with an initial velocity of 30 meters per second(v0)at an altitude of 402 meters(s). approximetly how long does it take the coin

Algebra ->  Quadratic Equations and Parabolas -> SOLUTION: use 4.9t^2 + vot = s a coin is tossed downward with an initial velocity of 30 meters per second(v0)at an altitude of 402 meters(s). approximetly how long does it take the coin      Log On


   



Question 234421: use 4.9t^2 + vot = s

a coin is tossed downward with an initial velocity of 30 meters per second(v0)at an altitude of 402 meters(s). approximetly how long does it take the coin to reach the ground?

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
use 4.9t^2 + vot = s
a coin is tossed downward with an initial velocity of 30 meters per second(v0)at an altitude of 402 meters(s). approximately how long does it take the coin to reach the ground?
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-4.9t^2-30t = -402 meters
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4.9t^2 + 30t -402 = 0
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Use Quadratic formula:
t = [-30 +- sqrt(900 - 4*4.9*-402)]/(9.8)
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t = [-30 +- sqrt(8779.2)]/9.8
Positive solution:
t = [-30+93.7]/9.2
t = 6.924 seconds
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Cheers,
Stan H.