document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=938340>Question 938340</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In a 3*3 grid, Id have put numbers from 1 to 9 so that the sum of the digits in the first row 11 , third row 18 , in the first column 21 and in the third column 17.\r<BR>\n" );
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document.write( "___  ____  ____ -11<BR>\n" );
document.write( "___  ____  _____<BR>\n" );
document.write( "___  ____  _____ -18\r<BR>\n" );
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document.write( "   -21    -     -17<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 #571589 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=571589\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Four equations, linear, in four unknown variables.  \r<BR>\n" );
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document.write( "Your chart is confusing and not just like the description, so the equations could be:\r<BR>\n" );
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document.write( "w+x=11<BR>\n" );
document.write( "y+z=18<BR>\n" );
document.write( "w+y=21<BR>\n" );
document.write( "x+z=17\r<BR>\n" );
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document.write( "The description does not indicate negative constants.\r<BR>\n" );
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document.write( "Substitution throughout could work, but you might want to uses elementary row operations for the equations in a form,  aw+bx+cy+dz=k,  for the variables w, x, y, z.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=z=17-x ALIGN=MIDDLE  ALT=\"z=17-x\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y%2B17-x=18 ALIGN=MIDDLE  ALT=\"y%2B17-x=18\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y-x=1 ALIGN=MIDDLE  ALT=\"y-x=1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Newer system<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28w%2Bx=11%2C-x%2By=1%2Cw%2By=21%29 ALIGN=MIDDLE  ALT=\"system%28w%2Bx=11%2C-x%2By=1%2Cw%2By=21%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Take that middle equation, and use <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=x%2B1 ALIGN=MIDDLE  ALT=\"y=x%2B1\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28w%2Bx=11%2Cw%2Bx%2B1=21%29 ALIGN=MIDDLE  ALT=\"system%28w%2Bx=11%2Cw%2Bx%2B1=21%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Contradictory, w+x=11 and w+x=20, cannot be! </SPAN>\n" );
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