Question 992194
A person standing close to the edge on the top of a 270-foot building throws a baseball vertically upward. The quadratic equation 
 h = -16 t^2 + 160 t + 270 
 models the ball's height h above the ground in feet, t seconds after it was thrown. 
 How high is the ball after 5 seconds? 
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h(t) = -16t^2 + 160t + 270
Find h(5) = sub 5 for t.
h(5) is 670 feet.
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 How many seconds does it take until the ball finally hits the ground? Round to the nearest tenth of a second.
h(t) = -16t^2 + 160t + 270
-16t^2 + 160t + 270 = 0
Solve for t.  Use the positive solution.
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*[invoke solve_quadratic_equation -16,160,270]
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t = 11.5 seconds.
Maybe you didn't use the nearest 10th ?