document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=758201>Question 758201</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose a football is kicked from the ground and its height in feet above the ground is given by h = -3.9t2 + 15.6t. The height above the ground is \"h\". The time in seconds, after the ball is kicked, is \"t\". How long is the ball in the air?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #461270 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=461270\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Suppose a football is kicked from the ground and its height in feet above the ground is given by h = -3.9t2 + 15.6t. The height above the ground is \"h\". The time in seconds, after the ball is kicked, is \"t\". How long is the ball in the air?<BR>\n" );
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document.write( "Solve -3.9t^2 + 15.6t = 0<BR>\n" );
document.write( "-3.5t(t - 4) = 0<BR>\n" );
document.write( "Positive solution:<BR>\n" );
document.write( "t = 4<BR>\n" );
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document.write( "In the air for 4 seconds.<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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