<PRE><B>Question 209449</B>
If a penny is thrown downward at 30 ft/sec
from the bridge at Royal Gorge, Colorado, how long does it
take to reach the Arkansas River 1000 ft below? 
It says to use the quadratic equation. 
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The height of an object (neglecting air friction) is
h(t) = -16t^2 + vt + h0 Where v is the starting speed and h0 is the initial height.  t is in seconds, h in feet.
In this case h0 = 1000 ft, and v = -30 ft/sec (-30 since it&#39;s thrown downward)
Find when h(t) = 0
0 = -16t^2 - 30t + 1000
-8t^2 - 15t + 500 = 0
*[invoke solve_quadratic_equation -8,-15,500]
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Use the positive value for t (it says x2)
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