document.write( "Question 236861: the height of an object projected upward from ground level is given by h+-16t^2+128t where h is in feet and t is time in seconds. when will the object be 240 feet above ground level ...\r
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Algebra.Com's Answer #174224 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
the height of an object projected upward from ground level is given by \"h=-16t%5E2%2B128t\" where h is in feet and t is time in seconds. when will the object be 240 feet above ground level ... \r
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document.write( "\"h=-16t%5E2%2B128t\"\r\n" );
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document.write( "Substitute 240 ft as the height h in the equation:\r\n" );
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document.write( "\"240=-16t%5E2%2B128t\"\r\n" );
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document.write( "Get 0 on the right:  \r\n" );
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document.write( "\"16t%5E2-128t%2B240=0\"\r\n" );
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document.write( "Divide every term by \"16\"\r\n" );
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document.write( "\"%2816t%5E2%29%2F16-%28128t%29%2F16%2B240%2F16=0\"\r\n" );
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document.write( "\"t%5E2-8t%2B15=0\"\r\n" );
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document.write( "Factor the left side:\r\n" );
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document.write( "\"%28t-3%29%28t-5%29=0\"\r\n" );
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document.write( "Set each factor = 0\r\n" );
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document.write( "Setting \"t-3=0%7D%7D%0D%0A++++++++%7B%7B%7Bt=3\" \r\n" );
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document.write( "Setting \"t-5=0\"\r\n" );
document.write( "        \"t=5\"\r\n" );
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document.write( "There are two solutions, because the\r\n" );
document.write( "object will be exactly 240 feet above\r\n" );
document.write( "the ground on its way UP exactly 3 \r\n" );
document.write( "seconds after it is projected upward. \r\n" );
document.write( "Then it will be 240 feet above the ground \r\n" );
document.write( "again on its way back DOWN 5 seconds \r\n" );
document.write( "after it is projected upward.  So the \r\n" );
document.write( "answer is both 3 seconds and 5 seconds\r\n" );
document.write( "after it is projected upward.\r\n" );
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document.write( "Edwin
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