document.write( "Question 1120740: A tennis ball is tossed vertically upward from a height of 5 metres according to the height equation\r
\n" ); document.write( "\n" ); document.write( "h= -16t^+21t+5,where h is the height of the tennis ball in metres and t is the time in second.\r
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Algebra.Com's Answer #736405 by josgarithmetic(39617)\"\" \"About 
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\"-16t%5E2%2B21t%2B5=11\"\r
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\n" ); document.write( "\n" ); document.write( "\"-16t%5E2%2B21t-6=0\"\r
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