document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=391152>Question 391152</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 2x+y-z=7<BR>\n" );
document.write( "2x-y+3z=13<BR>\n" );
document.write( "3x+2y-z=17 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #277454 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=277454\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Add the first two equations (this clears out the y-term) to get\r<BR>\n" );
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document.write( "4x + 2z = 20 --> 2x + z = 10\r<BR>\n" );
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document.write( "Multiply the second equation by 2, so we can add the second and third equations and also clear the y-terms. This results in another equation in terms of x and z that is not equivalent to the one we already obtained.\r<BR>\n" );
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document.write( "4x - 2y + 6z = 26<BR>\n" );
document.write( "3x + 2y - z = 17<BR>\n" );
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document.write( "7x + 5z = 43\r<BR>\n" );
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document.write( "We can rewrite this as 5(2x + z) - 3x = 43 --> 5(10) - 3x = 43 --> x = 7/3, z = 16/3. Substituting x and z into any of the equations, we get y = 23/3. Therefore the solution (x,y,z) is (7/3, 23/3, 16/3). </SPAN>\n" );
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