document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1152439>Question 1152439</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 3x+y-4z=-6<BR>\n" );
document.write( "2x+3y-4z=4<BR>\n" );
document.write( "x-y+2z=-4 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #774452 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=774452\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 3x+y-4z=-6<BR>\n" );
document.write( "2x+3y-4z=4<BR>\n" );
document.write( "x-y+ 2z=-4<BR>\n" );
document.write( "------------<BR>\n" );
document.write( "Multiply the 3rd eqn by 2 --> 2x - 2y + 4z = -8<BR>\n" );
document.write( "----<BR>\n" );
document.write( "Add that to the 1st and to the 2nd eqn.<BR>\n" );
document.write( "z is eliminated.<BR>\n" );
document.write( "You have 2 eqns in x & y.<BR>\n" );
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document.write( "<PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">\r\n" );
document.write( "3x +  y - 4z = -6\r\n" );
document.write( "2x - 2y + 4z = -8\r\n" );
document.write( "------------------------------ Add\r\n" );
document.write( "5x - y = -14  ----  Eqn A\r\n" );
document.write( "==========================\r\n" );
document.write( "2x + 3y - 4z = 4\r\n" );
document.write( "2x - 2y + 4z = -8\r\n" );
document.write( "------------------------------- Add\r\n" );
document.write( "4x + y = -4  ----   Eqn B\r\n" );
document.write( "============================\r\n" );
document.write( "5x - y = -14  ----  Eqn A\r\n" );
document.write( "4x + y = -4  ----   Eqn B\r\n" );
document.write( "-------------------------------- Add\r\n" );
document.write( "9x = -18\r\n" );
document.write( "x = -2\r\n" );
document.write( "=============\r\n" );
document.write( "4x + y = -4  ----   Eqn B\r\n" );
document.write( "-8 + y = -4\r\n" );
document.write( "y = 4\r\n" );
document.write( "=====================\r\n" );
document.write( "3x+y-4z=-6  -------- 1st eqn\r\n" );
document.write( "-6 + 4 - 4z = -6\r\n" );
document.write( "4z = 4\r\n" );
document.write( "z = 1\r\n" );
document.write( "----> (-2,4,1)\r\n" );
document.write( "</PRE><BR>\n" );
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document.write( "Mathlover used substitution.<BR>\n" );
document.write( "I think that takes more work (in this case) than elimination.<BR>\n" );
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document.write( "I would use a matrix because I have an Excel sheet that does those, but it doesn't teach anything, just gives the answers.<BR>\n" );
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