Question 473190
 The equation h=-16t^2-64t+250 (i used the symbol ^ to represent t squared) gives the height of a ball, thrown
downward from the top of a 250-ft building with an initial velocity of 64 ft/s.
Find the time it takes for the ball to reach a height of 100 ft. Round your answer to the nearest thousandth.
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Set the height equal to 100 and solve for "t":
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-16t^2-64t+250  = 100
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-16t^2-64t + 150 = 0
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Divide thru by -2 to get:
8t^2 + 32t - 75 = 0
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Use the quadratic formula to get:
t = 1.657 seconds
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Cheers,
Stan H.
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