SOLUTION: Science and medicine:
A ball is thrown upward from the roof of a building 100m tall width the initial velocity of 20 m/s. When will the ball reach the height of 80 m?
I would
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A ball is thrown upward from the roof of a building 100m tall width the initial velocity of 20 m/s. When will the ball reach the height of 80 m?
I would
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Question 121302: Science and medicine:
A ball is thrown upward from the roof of a building 100m tall width the initial velocity of 20 m/s. When will the ball reach the height of 80 m?
I would really appreciate some help on this, Thank you very much. Answer by Nate(3500) (Show Source):
You can put this solution on YOUR website! h(t) = -16t^2 + 20t + 100
80 = -16t^2 + 20t + 100
0 = -16t^2 + 20t + 20
0 = -4t^2 + 5t + 5
t = ( -5 +- sqrt( 25 + 4*4*5 ) ) / (-2*4)
t = ( 5 +- sqrt( 105 ) ) / 8
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