SOLUTION: An object is thrown into the air at 80ft/sec.. If the height "h" of the object after "t" seconds of traveling is given by h=80t-16t^2, find out when this object hits the ground. (

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Question 526218: An object is thrown into the air at 80ft/sec.. If the height "h" of the object after "t" seconds of traveling is given by h=80t-16t^2, find out when this object hits the ground. (Remember: ground is h=0)
Found 2 solutions by htmentor, Alan3354:
Answer by htmentor(1343) About Me  (Show Source):
You can put this solution on YOUR website!
An object is thrown into the air at 80ft/sec.. If the height "h" of the object after "t" seconds of traveling is given by h=80t-16t^2, find out when this object hits the ground. (Remember: ground is h=0)
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Setting h=0 in the above equation gives:
80t - 16t^2 = 0
Dividing through by the GCF(=16) and factoring the remaining expression gives:
t(5 - t) = 0
The two solutions are t=0 (the moment it is thrown) and t=5 (when it returns to the ground)
Ans: t = 5 sec

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
When 80t - 16t^2 = 0.
Solve for t.