document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1140945>Question 1140945</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve: use the Gausd-Jordan elimination (RREF)\r<BR>\n" );
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document.write( "-3   1  -1   4<BR>\n" );
document.write( " 2  -1   1  -8<BR>\n" );
document.write( " 4  -3   2  12 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #761489 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=761489\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \r<BR>\n" );
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document.write( "Your matrix\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=matrix%283%2C4%2C%0D%0A-3%2C%091%2C%09-1%2C%094%2C%0D%0A2%2C%09-1%2C%091%2C%09-8%2C%0D%0A4%2C%09-3%2C%092%2C%0912%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Make the pivot in the 1st column by dividing the 1st row by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-3 ALIGN=MIDDLE  ALT=\"-3\"   DISABLED_style= \"max-width:90%; height:auto;\" >:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=matrix%283%2C4%2C%0D%0A1%2C%09-1%2F3%2C%091%2F3%2C%09-4%2F3%2C%0D%0A2%2C%09-1%2C%091%2C%09-8%2C%0D%0A4%2C%09-3%2C%092%2C%0912%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Eliminate the 1st column:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=matrix%283%2C4%2C%0D%0A%0D%0A1%2C%09-1%2F3%2C%091%2F3%2C%09-4%2F3%2C%0D%0A0%2C%09-1%2F3%2C%091%2F3%2C%09-16%2F3%2C%0D%0A0%2C%09-5%2F3%2C%092%2F3%2C%0952%2F3%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Make the pivot in the 2nd column by dividing the 2nd row by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-1%2F3 ALIGN=MIDDLE  ALT=\"-1%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" >:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=matrix%283%2C4%2C%0D%0A1%2C%09-1%2F3%2C%091%2F3%2C%09-4%2F3%2C%0D%0A0%2C%091%2C%09-1%2C%0916%2C%0D%0A0%2C%09-5%2F3%2C%092%2F3%2C%0952%2F3%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Eliminate the 2nd column:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=matrix%283%2C4%2C%0D%0A%0D%0A1%2C%090%2C%090%2C%094%2C%0D%0A0%2C%091%2C%09-1%2C%0916%2C%0D%0A0%2C%090%2C%09-1%2C%0944%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Find the pivot in the 3rd column in the 3rd row (inversing the sign in the whole row)\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=matrix%283%2C4%2C%0D%0A1%2C%090%2C%090%2C%094%2C%0D%0A0%2C%091%2C%09-1%2C%0916%2C%0D%0A0%2C%090%2C%091%2C%09-44%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Eliminate the 3rd column:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=matrix%283%2C4%2C%0D%0A%0D%0A1%2C%090%2C%090%2C%094%2C%0D%0A0%2C%091%2C%090%2C%09-28%2C%0D%0A0%2C%090%2C%091%2C%09-44%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Solution set:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5B2%5D+=+-28 ALIGN=MIDDLE  ALT=\"x%5B2%5D+=+-28\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5B3%5D+=+-44 ALIGN=MIDDLE  ALT=\"x%5B3%5D+=+-44\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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