document.write( "Question 989590: Hi, I have a problem that deals with linear equations with three variables:
\n" ); document.write( "SOLVE:
\n" ); document.write( "x+y=7
\n" ); document.write( "y+z=8
\n" ); document.write( "x+2z=2\r
\n" ); document.write( "\n" ); document.write( "and no, I cannot simply use matrices to solve this question. I tried eliminating 'z' from the second and third equation, but I got stuck because I can't eliminate 'z' from the first equation. Please help and thank you so much to whoever helps! \n" ); document.write( "
Algebra.Com's Answer #609880 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
SOLVE:
\n" ); document.write( "x+y=7
\n" ); document.write( "y+z=8
\n" ); document.write( "x+2z=2
\n" ); document.write( "----
\n" ); document.write( "express y and x in terms of \"z\"::
\n" ); document.write( "y = 8-z
\n" ); document.write( "x = 2-2z
\n" ); document.write( "------
\n" ); document.write( "Substitute for x and y and solve for \"z\"::
\n" ); document.write( "2-2z + 8-z = 7
\n" ); document.write( "-3z + 10 = 7
\n" ); document.write( "-3z = -3
\n" ); document.write( "z = 1
\n" ); document.write( "----
\n" ); document.write( "y = 8-z = 7
\n" ); document.write( "x = 2 - 2z = 2-2 = 0
\n" ); document.write( "----------
\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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