document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=61100>Question 61100</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Instructions: Solve each system by the substitution method.\r<BR>\n" );
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document.write( "What is the solution for 3x+y=-7<BR>\n" );
document.write( "                         x-y=-5 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #42046 by </B><A HREF=/tutors/aboutme.mpl?userid=jai_kos><B>jai_kos(139)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jai_kos><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=42046\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solution:\r<BR>\n" );
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document.write( "Given  \r<BR>\n" );
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document.write( "3x + y = -7              &#61664;(1)<BR>\n" );
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document.write( "x - y = -5               &#61664;(2)\r<BR>\n" );
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document.write( "Consider equation (2), we can rewrite the equation (2) as\r<BR>\n" );
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document.write( "x + 5 = y                &#61664;(3)\r<BR>\n" );
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document.write( "Substitute the equation (3) in equation (1), we get\r<BR>\n" );
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document.write( "3x + (x + 5) = - 7\r<BR>\n" );
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document.write( "3x + x + 5 = -7\r<BR>\n" );
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document.write( "4x + 5 = -7\r<BR>\n" );
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document.write( "4x = - 7 – 5\r<BR>\n" );
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document.write( "4x = -12\r<BR>\n" );
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document.write( "x = -12 / 4\r<BR>\n" );
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document.write( "x = -3                   &#61664;(4)\r<BR>\n" );
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document.write( "Put x = -3 in equation (1), we get\r<BR>\n" );
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document.write( "3(-3) + y = -7\r<BR>\n" );
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document.write( "-9 + y = - 7\r<BR>\n" );
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document.write( "y =  - 7 + 9\r<BR>\n" );
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document.write( "y = 2\r<BR>\n" );
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document.write( "Therefore the value of x = -3 and y = 2 \r<BR>\n" );
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document.write( " </SPAN>\n" );
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