document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=136221>Question 136221</A>: <I><SPAN STYLE=\"word-break: break-all;\"> SOLVE THE SYSTEM USING THE GAUSS-JORDAN METHOD<BR>\n" );
document.write( "PROBLEM: x-2y= -1<BR>\n" );
document.write( "        2x+y= -7<BR>\n" );
document.write( "PLEASE HELP SOLVE.. I UNDERSTAND THE FORMULA COMPLETLY AND HOW IT SHOULD COME OUT TO LOOK LIKE [ 1 0.. AND BENEATH THAT 0 1..] YET JUST THE PROCESS OF SOLVING IT LOSES ME.. I DO UNDERSTAND HOW TO SET IT UP THOUGH<BR>\n" );
document.write( "[ 1 -2..-1]<BR>\n" );
document.write( "[2 1..-7]    THANK YOU FOR YOUR TIME... lj23kfuller@yahoo.com </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #99777 by </B><A HREF=/tutors/aboutme.mpl?userid=dolly><B>dolly(163)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=dolly><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=99777\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I'll help you\r<BR>\n" );
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document.write( "You got the matrix [1   2   -1]<BR>\n" );
document.write( "                   [2   1   -7]\r<BR>\n" );
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document.write( "Now we perform row operations basically to make the elements below and above the principal diagonal as 0\r<BR>\n" );
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document.write( "Consider R2 - 2 R1<BR>\n" );
document.write( "So the matrix becomes   [1   2   -1]<BR>\n" );
document.write( "                        [0  -3   -5]\r<BR>\n" );
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document.write( "Now the element below the diagonal became 0\r<BR>\n" );
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document.write( "To get the elemnts along the diagonal as 1,<BR>\n" );
document.write( "we divide the R2 by -3\r<BR>\n" );
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document.write( "==>       [1   2   -1]<BR>\n" );
document.write( "          [0   1   -5/-3]\r<BR>\n" );
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document.write( "=         [1   2    -1]<BR>\n" );
document.write( "          [0   1    5/3]\r<BR>\n" );
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document.write( "Now to make the element above the diagonal 0, perform\r<BR>\n" );
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document.write( "R1 - 2 R2\r<BR>\n" );
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document.write( "==>       [1   0   -1-10/3]<BR>\n" );
document.write( "          [0   1     5/3]\r<BR>\n" );
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document.write( "==>       [1   0    -13/3]<BR>\n" );
document.write( "          [0   1      5/3]\r<BR>\n" );
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document.write( "This represents the original equation\r<BR>\n" );
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document.write( "Thus we get x = -13/3  and y = 5/3\r<BR>\n" );
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document.write( "These satisfy the given equation.\r<BR>\n" );
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document.write( "Hope it is clear\r<BR>\n" );
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document.write( "Good luck!!!\r<BR>\n" );
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document.write( "Dolly </SPAN>\n" );
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