document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1072213>Question 1072213</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How would you go about finding the solution to this system of three equations in three variables? \r<BR>\n" );
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document.write( "2x – y + z = 7\r<BR>\n" );
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document.write( "x + 2y – 5z = -1\r<BR>\n" );
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document.write( "x – y = 6 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #687105 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=687105\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 2x – y + z = 7 <BR>\n" );
document.write( "x + 2y – 5z = -1 <BR>\n" );
document.write( "x – y = 6 <BR>\n" );
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document.write( "x = 6+y<BR>\n" );
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document.write( "Substitute for \"x\" in the 1st and the 2nd equation<BR>\n" );
document.write( "to get two equations in y and z.<BR>\n" );
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document.write( "12+2y-y+z = 7<BR>\n" );
document.write( "6+y + 2y - 5z = -1<BR>\n" );
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document.write( "y + z = -5<BR>\n" );
document.write( "3y - 5z = -7<BR>\n" );
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document.write( "Modify::<BR>\n" );
document.write( "3y + 3z = -15<BR>\n" );
document.write( "3y - 5z = -7<BR>\n" );
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document.write( "Subtract and solve for \"z\":<BR>\n" );
document.write( "8z = 8<BR>\n" );
document.write( "z = 1<BR>\n" );
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document.write( "Then solve for \"y\".<BR>\n" );
document.write( "Then solve for \"x\".<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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