document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1169155>Question 1169155</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Subscript notation is frequently used for working with larger systems of equations. Use a matrix approach to solve the system. Express the solutions as 4-tuples of the form <BR>\n" );
document.write( "(x1, x2, x3, x4).\r<BR>\n" );
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document.write( "x1 − 3x2 − 2x3 + x4	 = 	−4<BR>\n" );
document.write( "−2x1 + 7x2 + x3 − 2x4	 = 	−2<BR>\n" );
document.write( "3x1 − 7x2 − 3x3 + 3x4	 = 	−5<BR>\n" );
document.write( "5x1 + x2 + 4x3 − 2x4	 = 	20\r<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 #794157 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13203)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=794157\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "\"Use a matrix approach\" means to me one of three possibilities:<BR>\n" );
document.write( "A graphing calculator;<BR>\n" );
document.write( "Gauss-Jordan elimination;<BR>\n" );
document.write( "Cramer's Rule.<br><BR>\n" );
document.write( "All three of those methods are well defined.  It does you no good to have us do the work for you and tell you the answer; and it uses a lot of our valuable time.<br><BR>\n" );
document.write( "Choose a method (the graphing calculator is by far the easiest!) and work the problem yourself.<br><BR>\n" );
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