SOLUTION: A ball is thrown strait up, from 2m above the ground, with a velocity of 7 m/s. When does it hit the ground?

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Question 1075516: A ball is thrown strait up, from 2m above the ground, with a velocity of 7 m/s. When does it hit the ground?
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
The equation is -4.9x^2+7x+2=0
That is 4.9x^2-7x-2=0
x=(1/9.8)(7+/- sqrt (49+19.6); sqrt (68.6)=8.28
x=15.28/9.8 and -1.28/9, which will be ignored.
x=1.56 sec.
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