document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=770914>Question 770914</A>: <I><SPAN STYLE=\"word-break: break-all;\"> solve by substation<BR>\n" );
document.write( "x-y=10<BR>\n" );
document.write( "-x-y=20<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #469845 by </B><A HREF=/tutors/aboutme.mpl?userid=algebrahouse.com><B>algebrahouse.com(1659)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=algebrahouse.com><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=algebrahouse.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=469845\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> x - y = 10<BR>\n" );
document.write( "-x - y = 20\r<BR>\n" );
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document.write( "x = y + 10 {added y to each side of top equation}\r<BR>\n" );
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document.write( "-(y + 10) - y = 20 {substituted (y + 10), in for x, into bottom equation}<BR>\n" );
document.write( "-y - 10 - y = 20 {distributed negative sign through parentheses}<BR>\n" );
document.write( "-2y - 10 = 20 {combined like terms}<BR>\n" );
document.write( "-2y = 30 {added 10 to each side}<BR>\n" );
document.write( "y = -15 {divided each side by -2}\r<BR>\n" );
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document.write( "x = y + 10 {transformed top equation}<BR>\n" );
document.write( "x = -15 + 10 {substituted -15, in for y, into new top equation}<BR>\n" );
document.write( "x = -5 {combined like terms}\r<BR>\n" );
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document.write( "x = -5 and y = -15<BR>\n" );
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