document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=183507>Question 183507</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solving a system of four equations:\r<BR>\n" );
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document.write( "3a+2b+c-d=-5<BR>\n" );
document.write( "2a-5b+8c+2d=19<BR>\n" );
document.write( "7a+12b-3c=-5<BR>\n" );
document.write( "11a-7b=18 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #137777 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=137777\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> This site shows how to do, and it solves it for you.\r<BR>\n" );
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document.write( "http://www.math.odu.edu/~bogacki/cgi-bin/lat.cgi?c=sys<BR>\n" );
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document.write( "This works well, gives the answers so you can check your work.  You can write a computer program to do these (I did it years ago in Fortran), but I would use Excel and determinants to do it now.  I have an Excel sheet that does up to 4th order. </SPAN>\n" );
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