document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=302020>Question 302020</A>: <I><SPAN STYLE=\"word-break: break-all;\"> solve each system using the substitution method.<BR>\n" );
document.write( "x-2y=7<BR>\n" );
document.write( "3x-21=6y </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #216717 by </B><A HREF=/tutors/aboutme.mpl?userid=london+maths+tutor><B>london maths tutor(243)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=london+maths+tutor><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=london+maths+tutor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=216717\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> x-2y=7 ... equation 1<BR>\n" );
document.write( "3x-21=6y ... equation 2\r<BR>\n" );
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document.write( "Let's x = 1 \r<BR>\n" );
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document.write( "x-2y = 7 <BR>\n" );
document.write( "1 - 2y = 7 <BR>\n" );
document.write( "-2y = 7 -1 <BR>\n" );
document.write( "-2y = 6 <BR>\n" );
document.write( "y = -3\r<BR>\n" );
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document.write( "Put y = -3 and x = 1 into equation 2\r<BR>\n" );
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document.write( "3x - 21 = 6y <BR>\n" );
document.write( "3x - 6y = 21<BR>\n" );
document.write( "3(1) - 6(-3) = 21<BR>\n" );
document.write( "3 -(-18) = 21<BR>\n" );
document.write( "3 + 18 = 21<BR>\n" );
document.write( "21 = 21 \r<BR>\n" );
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document.write( "Therefore, x = 1 and y = -3  </SPAN>\n" );
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