document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=339926>Question 339926</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The fish population in a certain lake rises and falls according to<BR>\n" );
document.write( "the formula.      <BR>\n" );
document.write( "F=1000(30+15t-t2).\r<BR>\n" );
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document.write( "Here  F is the number of fish at a time t  , where t  is measured in years <BR>\n" );
document.write( "since January 1, 2002. Use this information to answer the following<BR>\n" );
document.write( "questions.\r<BR>\n" );
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document.write( "1. The fish population will again be the same as on January 1, 2002<BR>\n" );
document.write( "on the date January 1,_________(that is____________ years later).\r<BR>\n" );
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document.write( "2. All the fish in the lake will die after 'approximately' \r<BR>\n" );
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document.write( "      t=_________________years (the answer might be a decimal numbers) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #243618 by </B><A HREF=/tutors/aboutme.mpl?userid=jrfrunner><B>jrfrunner(365)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jrfrunner><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=jrfrunner><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=243618\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=F=1000%2830%2B15t-t%5E2%29 ALIGN=MIDDLE  ALT=\"F=1000%2830%2B15t-t%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "==<BR>\n" );
document.write( "1. The fish population will again be the same as on January 1, 2002\r<BR>\n" );
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document.write( "January 1,2002 means t=0<BR>\n" );
document.write( "when t=0, F=30,000<BR>\n" );
document.write( "so you want to know when <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=F=30000=1000%2830%2B15t-t%5E2%29 ALIGN=MIDDLE  ALT=\"F=30000=1000%2830%2B15t-t%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "which means <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=30000%2F1000=30%2B15t-t%5E2 ALIGN=MIDDLE  ALT=\"30000%2F1000=30%2B15t-t%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0=15t-t%5E2=%2815-t%29t ALIGN=MIDDLE  ALT=\"0=15t-t%5E2=%2815-t%29t\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "t=0 or t=15<BR>\n" );
document.write( "answer t=15 years from Jan 1, 2002 or January 1, 2017<BR>\n" );
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document.write( "2. All the fish in the lake will die after 'approximately' <BR>\n" );
document.write( "You basically want to know t, for F=0<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=F=1000%2830%2B15t-t%5E2%29 ALIGN=MIDDLE  ALT=\"F=1000%2830%2B15t-t%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0=1000%2830%2B15t-t%5E2%29 ALIGN=MIDDLE  ALT=\"0=1000%2830%2B15t-t%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0=30%2B15t-t%5E2 ALIGN=MIDDLE  ALT=\"0=30%2B15t-t%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "use quadratic equation  with a=-1, b=15, c=30<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=%28-15-sqrt%2815%5E2-4%28-1%2930%29%29%2F%282%28-1%29%29=16.79 ALIGN=MIDDLE  ALT=\"t=%28-15-sqrt%2815%5E2-4%28-1%2930%29%29%2F%282%28-1%29%29=16.79\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=%28-15%2Bsqrt%2815%5E2-4%28-1%2930%29%29%2F%282%28-1%29%29=-1.79 ALIGN=MIDDLE  ALT=\"t=%28-15%2Bsqrt%2815%5E2-4%28-1%2930%29%29%2F%282%28-1%29%29=-1.79\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "answer: 16.79 years after january 1, 2002 or roughly Sept 14,2018 </SPAN>\n" );
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