document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=633334>Question 633334</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve this system of linear equations using matrices.\r<BR>\n" );
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document.write( "x  +  y      = 3<BR>\n" );
document.write( "     2y      = 10<BR>\n" );
document.write( "3x + 2y - 4z = 12\r<BR>\n" );
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document.write( "The answer is (-2, 5, 2); I want someone to walk me through this problem, because I'm just not able to solve it correctly using row operations. Here's my work:\r<BR>\n" );
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document.write( "1        1        0        3\r<BR>\n" );
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document.write( "0        2        0        10\r<BR>\n" );
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document.write( "3        2       -4        12\r<BR>\n" );
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document.write( "1        1        0        3\r<BR>\n" );
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document.write( "0        2/2      0        10/2\r<BR>\n" );
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document.write( "3        2       -4        12\r<BR>\n" );
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document.write( "      1             1            0            3\r<BR>\n" );
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document.write( "      0             1            0            5\r<BR>\n" );
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document.write( "-3(1)+3       -3(1)+2           -4      -3(3)+12\r<BR>\n" );
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document.write( "1           1            0            3\r<BR>\n" );
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document.write( "0           1            0            5\r<BR>\n" );
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document.write( "0        1(1)-1         -4           1(3)+3\r<BR>\n" );
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document.write( "1           1           0           3\r<BR>\n" );
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document.write( "0           1           0           5\r<BR>\n" );
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document.write( "0           0         -4/-4        6/-4\r<BR>\n" );
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document.write( "1        1        0        3\r<BR>\n" );
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document.write( "0        1        0        2\r<BR>\n" );
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document.write( "0        0        1      -6/4 \r<BR>\n" );
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document.write( "I got z = -6/4, but it's supposed to equal 2... what am I doing wrong? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #398837 by </B><A HREF=/tutors/aboutme.mpl?userid=richwmiller><B>richwmiller(17219)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richwmiller><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=richwmiller><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=398837\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Actually the answer is -2, 5, -2 not  -2, 5, 2<BR>\n" );
document.write( "I don't know where you went wrong but after you found y=5<BR>\n" );
document.write( "You could have gotten x=-2<BR>\n" );
document.write( "1 1 0 3 <BR>\n" );
document.write( "0 1 0 5 <BR>\n" );
document.write( "1 0 0 -2\r<BR>\n" );
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document.write( "now we have <BR>\n" );
document.write( "1 0 0-2<BR>\n" );
document.write( "0 1 0 5 <BR>\n" );
document.write( "3 2 -4 12 <BR>\n" );
document.write( "3 0 0 -6<BR>\n" );
document.write( "0 2 -4 18<BR>\n" );
document.write( "0 2 0 10 <BR>\n" );
document.write( "0 0 -4 8<BR>\n" );
document.write( "which leaves<BR>\n" );
document.write( "0 0 1 -2 </SPAN>\n" );
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