document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=887568>Question 887568</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve the system of equations using matrices. Use Gaussian elimination with back-substituting or Gauss-Jordan elimination. \r<BR>\n" );
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document.write( "x-9y-z=-17<BR>\n" );
document.write( "x-y+z=7<BR>\n" );
document.write( "x+y-z=3 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #536729 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39620)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=536729\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28matrix%283%2C4%2C%0D%0A1%2C-9%2C-1%2C-17%2C%0D%0A1%2C-1%2C1%2C7%2C%0D%0A1%2C1%2C-1%2C3%0D%0A%29%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "R2=R2-R1, R3=R3-R1\r<BR>\n" );
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document.write( "R2=(1/8)R2, R3=(1/10)R3\r<BR>\n" );
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document.write( "Notice that already we have y=2.\r<BR>\n" );
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document.write( "Switch R2 and R3\r<BR>\n" );
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document.write( "R3=R3-R2\r<BR>\n" );
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document.write( "Multiply R3 by 4.\r<BR>\n" );
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document.write( "R1=R3+R1<BR>\n" );
document.write( "and then<BR>\n" );
document.write( "R1=9*R2+R1\r<BR>\n" );
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document.write( "---<BR>\n" );
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document.write( "x=-7<BR>\n" );
document.write( "y=2<BR>\n" );
document.write( "z=8 </SPAN>\n" );
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