SOLUTION: An object is projected upward from the top of a 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

Algebra ->  Rational-functions -> SOLUTION: An object is projected upward from the top of a 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       Log On


   

Question 45908: An object is projected upward from the top of a 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 level?
Answer by Nate(3500) About Me  (Show Source):
You can put this solution on YOUR website!
s(t) = -16t^2 + 64t + 80
x+=+%28-b+%2B-+sqrt%28+b%5E2+-+4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x+=+%28-64+%2B-+sqrt%28+64%5E2+%2B+4%2A%2816%29%2A%2880%29+%29%29%2F%28-32%29+
x+=+%28-64+%2B-+sqrt%28+64%5E2+%2B+4%2A%2816%29%2A%2880%29+%29%29%2F%28-32%29+
x+=+%28-64+%2B-+96%29%2F%28-32%29+
x+=+%28-64+%2B+96%29%2F%28-32%29+ and x+=+%28-64+-+96%29%2F%28-32%29+
x+=+%2832%29%2F%28-32%29+ and x+=+%28-160%29%2F%28-32%29+
x+=+-1 and x+=+5
+graph%28600%2C600%2C-10%2C10%2C-10%2C10%2C-16x%5E2%2B64x%2B80%29+