Problema Solution

The height h in meters of a ball t seconds after being tossed upward is given by the formula h-84t-16t2. after how many seconds will the ball reach a height of 80 meters for the second time?

Answer provided by our tutors

h = 84t - 16t^2

We need to find t such that h = 80 m that is, we need to solve the equation:

84t - 16t^2 = 80

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click here to see the equation solved for t

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t1 = 4 s

t2 = 1.25 s

The ball will reach height of 80 meters for the second time after 4 seconds.