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ashleyb
if a football player passes a football from 4 ft. off the ground with an initial velocity of 36 ft. per sec. how long will it take the football to hit the ground? use the equation h=-16t^2+36t+4
the height of the ground is zero, I think. So I would just sub in 0 for h then solve for t. One of the answers might not make sense (i.e. negative time) so toss that one out.
There is probably a simpler way than using the quadratic formula, but I'm lazy so... I just plugged the numbers in: a = -16 b = 36 c = 4 and got my 2 answers, one of them happened to be negative so I tossed it out, the other was (9+sqrt(97))/8 which I forced my calculator to approximate to 2.356 seconds. That would be my answer.