document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1113207>Question 1113207</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The height of ball that is launched from an initial of 84 feet with an initial upward velocity of 20 feet per second is given by the function:\r<BR>\n" );
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document.write( "h(t)= -16t^2+20t+84\r<BR>\n" );
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document.write( "where h represents the height of the ball at t seconds.  How long will it take for the ball to hit the ground? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #728207 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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/cgi-bin/show-face.mpl?user=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=728207\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \r<BR>\n" );
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document.write( "h(t)= <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-16t%5E2%2B20t%2B84 ALIGN=MIDDLE  ALT=\"-16t%5E2%2B20t%2B84\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "when it hits the ground h(t) =0\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-16t%5E2%2B20t%2B84 ALIGN=MIDDLE  ALT=\"-16t%5E2%2B20t%2B84\"   DISABLED_style= \"max-width:90%; height:auto;\" >=0\r<BR>\n" );
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document.write( "solve the quadratic equation.\r<BR>\n" );
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document.write( "4t^2 -5t-21=0\r<BR>\n" );
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document.write( "4t^2 -12t+7t-21=0\r<BR>\n" );
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document.write( "4t(t-3) +7(t-3)=0<BR>\n" );
document.write( "(t-3)(4t+7)=0\r<BR>\n" );
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document.write( "t= 3 <BR>\n" );
document.write( "after 3 seconds\r<BR>\n" );
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document.write( " </SPAN>\n" );
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