document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=178546>Question 178546</A>: <I><SPAN STYLE=\"word-break: break-all;\"> N=x^ +2 \r<BR>\n" );
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document.write( "this models the number of cases of an infection  in millions of a disease x represents the number of years how do I solve for how many years will there be 7 millon cases </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #133506 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=133506\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font face=\"Times New Roman\" size=\"+2\">\r<BR>\n" );
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document.write( "I presume you mean the model to be <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large N = x^2 + 2\">  ('^' does not mean 'squared', it means 'raise to the power of' and you have to specify the power.  If you mean squared, then you need to write 'x^2'  Ok?)\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \text{          } N = x^2 + 2\">\r<BR>\n" );
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document.write( "Substitute 7 for N:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \text{          } 7 = x^2 + 2\">\r<BR>\n" );
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document.write( "Add -2 to both sides:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \text{          } 7 - 2 = x^2\">\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \text{          } 5 = x^2\">\r<BR>\n" );
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document.write( "Take the positive square root:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \text{          } x = \LARGE sqrt{5}\"> years.\r<BR>\n" );
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document.write( "That is the exact answer.  A numerical approximation is two years, two months, and 25 days.\r<BR>\n" );
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