document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1161300>Question 1161300</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The population of a town is modelled by the function P=6t^2+110t+4000<BR>\n" );
document.write( "Where P is the population and t is the time in years since 2000.\r<BR>\n" );
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document.write( "a) What will the population be in 2020?\r<BR>\n" );
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document.write( "b) When will the population be 6000? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #784806 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=784806\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> ---------------------------------------------<BR>\n" );
document.write( "a) What will the population be in 2020?<BR>\n" );
document.write( "b) When will the population be 6000?<BR>\n" );
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document.write( "(a)\r<BR>\n" );
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document.write( "Substitute 20 for t, and just evaluate P.\r<BR>\n" );
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document.write( "(b)\r<BR>\n" );
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document.write( "Substitute 6000 for P, and solve for t.\r<BR>\n" );
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document.write( "You might find two \"solutions\" for part b.  Make the choice for the one which obviously makes sense.\r<BR>\n" );
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document.write( "WHEN WILL THE POPULATION BE 6000?\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6t%5E2%2B110t%2B4000=6000 ALIGN=MIDDLE  ALT=\"6t%5E2%2B110t%2B4000=6000\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "You know how to start; right?\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6t%5E2%2B110t%2B4000-6000=0 ALIGN=MIDDLE  ALT=\"6t%5E2%2B110t%2B4000-6000=0\"   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=6t%5E2%2B110t-2000=0 ALIGN=MIDDLE  ALT=\"6t%5E2%2B110t-2000=0\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "You know this can be simplified at least a little;\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3t%5E2%2B55t-1000=0 ALIGN=MIDDLE  ALT=\"3t%5E2%2B55t-1000=0\"   DISABLED_style= \"max-width:90%; height:auto;\" >--------and you know what to do with this (If possible, factoirze, but otherwise there is general solution for quadratic equation.)  Pick the result that makes sense!\r<BR>\n" );
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document.write( "You correctly solved for t.  The negative value has no meaning here.  The POSITIVE value found is the one which makes sense. </SPAN>\n" );
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