document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=831437>Question 831437</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A person standing close to the edge on the top of a 264 foot building throws a baseball vertically upward. The quadratic equation\r<BR>\n" );
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document.write( "h=-16t^2+64t+264\r<BR>\n" );
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document.write( "models the ball's height  above the ground in feet,  seconds after it was thrown.\r<BR>\n" );
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document.write( "How high is the ball after 2 seconds?\r<BR>\n" );
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document.write( "How many seconds does it take until the ball finally hits the ground? Round to the nearest tenth of a second.\r<BR>\n" );
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document.write( "I got the first part but can't figure out the second. <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #501388 by </B><A HREF=/tutors/aboutme.mpl?userid=KMST><B>KMST(5328)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=KMST><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=KMST><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=501388\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The ball hits the ground when <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=h=0 ALIGN=MIDDLE  ALT=\"h=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > so we solve<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-16t%5E2%2B64t%2B264=0 ALIGN=MIDDLE  ALT=\"-16t%5E2%2B64t%2B264=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Dividing both sides of the equation by 8, it becomes<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-2t%5E2%2B8t%2B33=0 ALIGN=MIDDLE  ALT=\"-2t%5E2%2B8t%2B33=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Using the quadratic formula we find two solutions given by<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-8+%2B-+sqrt%288%5E2-4%2A%28-2%29%2A33+%29%29%2F%282%2A%28-2%29%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-8+%2B-+sqrt%288%5E2-4%2A%28-2%29%2A33+%29%29%2F%282%2A%28-2%29%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-8+%2B-+sqrt%2864%2B264%29%29%2F%28-4%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-8+%2B-+sqrt%2864%2B264%29%29%2F%28-4%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-8+%2B-+sqrt%28328%29%29%2F%28-4%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-8+%2B-+sqrt%28328%29%29%2F%28-4%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%288+%2B-+sqrt%28328%29%29%2F4+ ALIGN=MIDDLE  ALT=\"t+=+%288+%2B-+sqrt%28328%29%29%2F4+\"   DISABLED_style= \"max-width:90%; height:auto;\" > .<BR>\n" );
document.write( "We take <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=%288%2Bsqrt%28328%29%29%2F4=%284%2Bsqrt%2882%29%29%2F2 ALIGN=MIDDLE  ALT=\"t=%288%2Bsqrt%28328%29%29%2F4=%284%2Bsqrt%2882%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > because the other solution is negative.<BR>\n" );
document.write( "The approximate value is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%286.53seconds%29 ALIGN=MIDDLE  ALT=\"highlight%286.53seconds%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > .<BR>\n" );
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document.write( "NOTES:<BR>\n" );
document.write( "Physics says that the person threw the ball up at an initial speed of<BR>\n" );
document.write( "64 ft/sec.<BR>\n" );
document.write( "Physics also says that the wording to the problem is wrong, because the equation says that the ball starts at 264 feet over the ground. That would be where the hand of the person standing close to the edge on the top of the building was as the ball left the hand. I would expect that hand to be 3 to 4 feet above the level the person is standing on. The problem did not need to mention the height of the building. </SPAN>\n" );
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