document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=667831>Question 667831</A>: <I><SPAN STYLE=\"word-break: break-all;\"> x+y=5 and xy=4 find x-y? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #415207 by </B><A HREF=/tutors/aboutme.mpl?userid=swincher4391><B>swincher4391(1107)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=swincher4391><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=swincher4391><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=415207\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> x+y =5  and xy=4\r<BR>\n" );
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document.write( "y = 5-x and plug into xy=4 to get:\r<BR>\n" );
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document.write( "x(5-x) = 4\r<BR>\n" );
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document.write( "5x - x^2 = 4\r<BR>\n" );
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document.write( "x^2 -5x +4 = 0\r<BR>\n" );
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document.write( "(x-1)(x-4) = 0 \r<BR>\n" );
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document.write( "x = 1 and x = 4\r<BR>\n" );
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document.write( "When x =1,  y = 4\r<BR>\n" );
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document.write( "When x =4, y =1\r<BR>\n" );
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document.write( "So in case 1:  x-y = 1-4 = -3\r<BR>\n" );
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document.write( "Case 2:  x-y = 4-1 = 3 </SPAN>\n" );
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