<PRE><B>Question 394017</B>
O’Brian of the Braves hits a Baseball straight upward at 150 ft/sec from a height of 5 ft.
a) Use the formula to determine how long it takes the ball
to return to the earth.
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h(t) = -16t^2+150t+5
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h(t) is zero when the ball in on the ground.
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Solve: -16t^2+150t+5 = 0
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t = [-150 +- sqrt(150^2-4*-16*5)]/(-32)
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t = [-150 +- sqrt(22820)]/(-32)
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Positive solution:
t = [-150-151.06]/(-32)
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t = 9.408 seconds
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Cheers,
Stan H.
</PRE>