document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=714545>Question 714545</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi!\r<BR>\n" );
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document.write( "x+y=2<BR>\n" );
document.write( "x*y=-15\r<BR>\n" );
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document.write( "Best regards<BR>\n" );
document.write( "Richard </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #438852 by </B><A HREF=/tutors/aboutme.mpl?userid=Simnepi><B>Simnepi(216)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Simnepi><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=Simnepi><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=438852\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> x+y=2    let's call this equation (1)<BR>\n" );
document.write( "x*y=-15    let's call this equation (2)<BR>\n" );
document.write( "from (1) we can deduce<BR>\n" );
document.write( "y=2-x <BR>\n" );
document.write( "let us substitute this value into (2) <BR>\n" );
document.write( "giving us<BR>\n" );
document.write( "x*(2-x)=-15<BR>\n" );
document.write( "multiplying out the bracket gives<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2x-x%5E2=-15 ALIGN=MIDDLE  ALT=\"2x-x%5E2=-15\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "rearranging this gives<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2-2x-15=0 ALIGN=MIDDLE  ALT=\"x%5E2-2x-15=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "now we have a quadratic to solve!<BR>\n" );
document.write( "(finding a factor pair of the constant term that will add to make the coefficient of the x term)<BR>\n" );
document.write( "this gives<BR>\n" );
document.write( "(x-5)(x+3)=0<BR>\n" );
document.write( "and we find our numbers to be<BR>\n" );
document.write( "5 and -3<BR>\n" );
document.write( "thus x=5 and y=-3 (or vice versa!) </SPAN>\n" );
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