document.write( "Question 322212: The equation h=-4t^2+16t+1.5 describes the path of a football, where t is the time in flight in seconds and h is the height of the football in metres.\r
\n" ); document.write( "\n" ); document.write( "How long is the football in the air (to the nearest second)? \n" ); document.write( "
Algebra.Com's Answer #230661 by stanbon(75887)\"\" \"About 
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The equation h=-4t^2+16t+1.5 describes the path of a football, where t is the time in flight in seconds and h is the height of the football in metres.
\n" ); document.write( "How long is the football in the air (to the nearest second)?
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\n" ); document.write( "The height is zero when the ball hits the ground.
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\n" ); document.write( "Solve -4t^2+16t+1.5 = 0
\n" ); document.write( "Quadratic Formula:
\n" ); document.write( "t = [-16 +- sqrt(16^2-4*-4*1.5)]/-8
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\n" ); document.write( "t = [-16 +- sqrt(280)]/-8
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\n" ); document.write( "Positive solution:
\n" ); document.write( "t = [-16-sqrt(280)]/-8
\n" ); document.write( "t = 4.0917 seconds
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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