Question 1058759
If a Baseball is thrown straight upward from level ground with an intial velocity of 72 ft/sec, its altitude s (in feet) after t seconds is given by s = -16t^2 + 72t. For what values of t will the ball be at least 32 feet above the ground?
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s = -16t^2 + 72t
For s = 32: -16t^2 + 72t = 32
Solve for t.
You get 2 times, one ascending, one descending.