document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=762488>Question 762488</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am really having troubles with these word problems.\r<BR>\n" );
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document.write( "an experimental drug is being tested on a bacteria colony. It is found that t days after treating the colony, the number N of bacteria per cubic centimeter is given by the equation N = 20t^2 -220t - 558. How long until the colony is reduced to 1482 bacteria<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 #464033 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=464033\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \r<BR>\n" );
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document.write( "use the equation <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N+=+20t%5E2+-220t+-+558 ALIGN=MIDDLE  ALT=\"N+=+20t%5E2+-220t+-+558\"   DISABLED_style= \"max-width:90%; height:auto;\" > and plug in <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N=1482 ALIGN=MIDDLE  ALT=\"N=1482\"   DISABLED_style= \"max-width:90%; height:auto;\" > bacteria\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1482+=+20t%5E2+-220t+-+558 ALIGN=MIDDLE  ALT=\"1482+=+20t%5E2+-220t+-+558\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+0=+20t%5E2+-220t+-+558-1482 ALIGN=MIDDLE  ALT=\"+0=+20t%5E2+-220t+-+558-1482\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+0=+20t%5E2+-220t+-+2040 ALIGN=MIDDLE  ALT=\"+0=+20t%5E2+-220t+-+2040\"   DISABLED_style= \"max-width:90%; height:auto;\" >.....all terms divide by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=20 ALIGN=MIDDLE  ALT=\"20\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+0=+20t%5E2%2F20+-220t%2F20+-+2040%2F20 ALIGN=MIDDLE  ALT=\"+0=+20t%5E2%2F20+-220t%2F20+-+2040%2F20\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+0=+t%5E2+-11t+-+102 ALIGN=MIDDLE  ALT=\"+0=+t%5E2+-11t+-+102\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%28-%28-11%29+%2B-+sqrt%28+%28-11%29%5E2-4%2A1%2A%28-102%29%29%29%2F%282%2A1%29+ ALIGN=MIDDLE  ALT=\"t+=+%28-%28-11%29+%2B-+sqrt%28+%28-11%29%5E2-4%2A1%2A%28-102%29%29%29%2F%282%2A1%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%2811+%2B-+sqrt%28121%2B408%29%29%2F2+ ALIGN=MIDDLE  ALT=\"t+=+%2811+%2B-+sqrt%28121%2B408%29%29%2F2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%2811+%2B-+sqrt%28529%29%29%2F2+ ALIGN=MIDDLE  ALT=\"t+=+%2811+%2B-+sqrt%28529%29%29%2F2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%2811+%2B-+23%29%2F2+ ALIGN=MIDDLE  ALT=\"t+=+%2811+%2B-+23%29%2F2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >......since we are looking for a time, we will find only positive value of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t ALIGN=MIDDLE  ALT=\"t\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+%2811+%2B+23%29%2F2+ ALIGN=MIDDLE  ALT=\"t+=+%2811+%2B+23%29%2F2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+34%2F2+ ALIGN=MIDDLE  ALT=\"t+=+34%2F2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t+=+17+ ALIGN=MIDDLE  ALT=\"t+=+17+\"   DISABLED_style= \"max-width:90%; height:auto;\" >  days until the colony is reduced to <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1482 ALIGN=MIDDLE  ALT=\"1482\"   DISABLED_style= \"max-width:90%; height:auto;\" > bacteria\r<BR>\n" );
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