document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=10830>Question 10830</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello! I posted this problem before, but nobody solved it. I'm really having trouble with this. Please help!<BR>\n" );
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document.write( "x + 2y + 16z = 20<BR>\n" );
document.write( "3x + 6y - z = 23<BR>\n" );
document.write( "4x + 8y + 2z = 18 \r<BR>\n" );
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document.write( "It doesn't matter which method you use to solve this system. Just please show me all the steps. Many thanks ahead! <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #5708 by </B><A HREF=/tutors/aboutme.mpl?userid=longjonsilver><B>longjonsilver(2297)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=longjonsilver><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=longjonsilver><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=5708\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> don't you realise how tedious matrices are? lol I hate them! I spent YEARS studying at uni doing damn matrices and linear algebra.\r<BR>\n" );
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document.write( "Anyway, here are 2 solutions ;-):\r<BR>\n" );
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document.write( "1. Gaussian Elimination:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=matrix%284%2C3%2C%0D%0A+++++++++1%2C+2%2C+16%2C+20%2C%0D%0A+++++++++3%2C+6%2C+-1%2C+23%2C%0D%0A+++++++++4%2C+8%2C+2%2C+18%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "OK, 3 times first row subtracted from second row<BR>\n" );
document.write( "and 4 times first row subtracted from third row<BR>\n" );
document.write( "gives\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=matrix%284%2C3%2C%0D%0A+++++++++1%2C+2%2C+16%2C+20%2C%0D%0A+++++++++0%2C+0%2C+-49%2C+-37%2C%0D%0A+++++++++0%2C+0%2C+-62%2C+-62%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Now, third row looks fine..will give z=1, but the second row looks wrong to me. I would go back to the question and check the numbers.\r<BR>\n" );
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document.write( "2. cramer's rule:<BR>\n" );
document.write( "(look on my Lessons for help on this)<BR>\n" );
document.write( "I wont do the working either, as i think your second equation is wrong.\r<BR>\n" );
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document.write( "jon. </SPAN>\n" );
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