document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=974854>Question 974854</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The difference between two numbers is &#8210;2.  The sum of the two numbers is 18.  Find the numbers.\r<BR>\n" );
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document.write( "I set up the equation as:<BR>\n" );
document.write( "x-y=-2<BR>\n" );
document.write( "x+y=18\r<BR>\n" );
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document.write( "I then isolated x by canceling out y:<BR>\n" );
document.write( "x=-2<BR>\n" );
document.write( "x=18<BR>\n" );
document.write( "x=16\r<BR>\n" );
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document.write( "then I tried to plug in 16 to the x variable to get y:<BR>\n" );
document.write( "x-y=-2       x+y=18<BR>\n" );
document.write( "16-y=-2      16+y=18<BR>\n" );
document.write( "-16 -16     -16  -16<BR>\n" );
document.write( "y=-18         y=2\r<BR>\n" );
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document.write( "What am i doing wrong? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #596666 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=596666\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The difference between two numbers is &#8210;2.  The sum of the two numbers is 18.  Find the numbers.\r<BR>\n" );
document.write( "\n" );
document.write( "I set up the equation as:<BR>\n" );
document.write( "x-y=-2<BR>\n" );
document.write( "x+y=18\r<BR>\n" );
document.write( "\n" );
document.write( "I then isolated x by canceling out y:<BR>\n" );
document.write( "x=-2<BR>\n" );
document.write( "x=18<BR>\n" );
document.write( "x=16\r<BR>\n" );
document.write( "\n" );
document.write( "then I tried to plug in 16 to the x variable to get y:<BR>\n" );
document.write( "x-y=-2       x+y=18<BR>\n" );
document.write( "16-y=-2      16+y=18<BR>\n" );
document.write( "-16 -16     -16  -16<BR>\n" );
document.write( "y=-18         y=2\r<BR>\n" );
document.write( "\n" );
document.write( "What am i doing wrong?<BR>\n" );
document.write( "=========================<BR>\n" );
document.write( "You can't just \"cancel out the y.\"  Where did you get that idea?<BR>\n" );
document.write( "Then, you get x = -2 (which is wrong)<BR>\n" );
document.write( "Then, x = 18 ?????<BR>\n" );
document.write( "Then, x = 16 ?<BR>\n" );
document.write( "================<BR>\n" );
document.write( "x-y=-2<BR>\n" );
document.write( "x+y=18<BR>\n" );
document.write( "------------------ Add them<BR>\n" );
document.write( "2x = 16<BR>\n" );
document.write( "x = 8<BR>\n" );
document.write( "y = 10<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );