document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1010629>Question 1010629</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The following is known about three numbers: If the second number is subtracted from the sum of the first number and 3 times the third number, the result is 2. The third number plus 3 times the first number is -1. The first number plus 3 times the second number plus the third number is -16. Find the sum of the three numbers.<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 #626081 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39618)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=626081\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The list of numbers, x, y, z.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28-y%2B%28x%2B3z%29=2%2Cz%2B3x=-1%2Cx%2B3y%2Bz=-16%29 ALIGN=MIDDLE  ALT=\"system%28-y%2B%28x%2B3z%29=2%2Cz%2B3x=-1%2Cx%2B3y%2Bz=-16%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Simplify the system.<BR>\n" );
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document.write( "Find the three numbers, x, y, z.<BR>\n" );
document.write( "Do what method you want or need to.  Elimination, substitution, matrix row reductions.\r<BR>\n" );
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document.write( "matrix?<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28matrix%283%2C4%2C%0D%0A1%2C-1%2C3%2C-2%2C%0D%0A3%2C0%2C1%2C-1%2C%0D%0A1%2C3%2C1%2C-16%29%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "R2=R2-3*R1, R3=R3-R1<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28matrix%283%2C4%2C%0D%0A1%2C-1%2C3%2C-2%2C%0D%0A0%2C3%2C-8%2C5%2C%0D%0A0%2C4%2C-2%2C-14%29%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "R3=(1/2)R3<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28matrix%283%2C4%2C%0D%0A1%2C-1%2C3%2C-2%2C%0D%0A0%2C3%2C-8%2C5%2C%0D%0A0%2C2%2C-1%2C-7%29%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Abbreviating some steps, working just with R2 and R3 using Elimination of y,<BR>\n" );
document.write( "...<BR>\n" );
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document.write( "and the matrix could look like<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28matrix%283%2C4%2C%0D%0A1%2C-1%2C3%2C-2%2C%0D%0A0%2C3%2C-8%2C5%2C%0D%0A0%2C0%2C1%2C-31%2F13%29%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "and you could use this to solve for y using R2.<BR>\n" );
document.write( "and...<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28y=-183%2F39%29 ALIGN=MIDDLE  ALT=\"highlight%28y=-183%2F39%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and...<BR>\n" );
document.write( "Using R1 to find x,<BR>\n" );
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