SOLUTION: please student in confusion....an object is projected upward from the top of tower. its distance in feet above the ground after t seconds is given by s(t)=-16t^2+64t+80. how

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Question 72977: please student in confusion....an object is projected upward from the top of tower. its distance in feet above the ground after t seconds is given by s(t)=-16t^2+64t+80. how many seconds will it take to reach ground.
Answer by funmath(2933)   (Show Source): You can put this solution on YOUR website!
an object is projected upward from the top of tower. its distance in feet above the ground after t seconds is given by s(t)=-16t^2+64t+80. how many seconds will it take to reach ground.
It's height will be 0 when it hits the ground, so set the problem = to 0.



Factor
set each factor = to 0 and solve for t.
t-5=0 or t+1=0
t-5+5=0+5 or t+1-1=0-1
t=5 or t=-1
Negative time is meaningless to us, so t=5 seconds.
Happy Calculating!!!!

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