document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=965591>Question 965591</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve the systems using the inverse matrix method:\r<BR>\n" );
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document.write( "5. {-3x + 9y =  9<BR>\n" );
document.write( "    { 3x + 2y = 13\r<BR>\n" );
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document.write( "6. { x + 2y + 3z = =8<BR>\n" );
document.write( "    { x +  y +   z = -11<BR>\n" );
document.write( "    {2x + 2y +  z = -2\r<BR>\n" );
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document.write( "Please help!  I am so lost on how to set these up.  Please show work so I can follow along. Thank you so much!  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #590196 by </B><A HREF=/tutors/aboutme.mpl?userid=hkwu><B>hkwu(60)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=hkwu><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=hkwu><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=590196\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I won't solve for this because it's tedious and you should be doing it yourself. The idea is to notice that if A is an invertible matrix, then<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\mathbf{A}\vec{x}=\vec{b}\"><BR>\n" );
document.write( "is equivalent to<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\vec{x}=\mathbf{A}^{-1}\vec{b}\"><BR>\n" );
document.write( "Thus, if you find <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\mathbf{A}^{-1}\"> then you can solve for <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\vec{x}\"> easily by multiplying <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\vec{b}\"> on the left by <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\mathbf{A}^{-1}\">.<BR>\n" );
document.write( "In case you don't know how to find the inverse of a matrix: write the coefficient matrix down and augment the other side of the matrix with the <IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?n\times n\"> identity matrix. Row reduce to reduced row echelon form on the left side. The right matrix will then be the inverse for the original matrix.<BR>\n" );
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document.write( "Leave a message if I helped. </SPAN>\n" );
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