document.write( "Question 198623: x+2y-z=3
\n" ); document.write( "2x-y+z=3
\n" ); document.write( "3x-4y+2z=-1 \n" ); document.write( "
Algebra.Com's Answer #149197 by ankor@dixie-net.com(22740)\"\" \"About 
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x + 2y - z = 3
\n" ); document.write( "2x - y + z = 3
\n" ); document.write( "3x -4y + 2z = -1
\n" ); document.write( ":
\n" ); document.write( "Multiply the 1st equation by 2, add to the 3rd equation
\n" ); document.write( "2x + 4y - 2z = 6
\n" ); document.write( "3x - 4y + 2z = -1
\n" ); document.write( "--------------------Addition eliminates y and z, find x:
\n" ); document.write( "5x = 5
\n" ); document.write( "x = 1
\n" ); document.write( ":
\n" ); document.write( "Replace x with 1 in the first two equations
\n" ); document.write( " 1 + 2y - z = 3
\n" ); document.write( "2(1) - y + z = 3
\n" ); document.write( ":
\n" ); document.write( "2y - z = 3 - 1
\n" ); document.write( "-y + z = 3 - 2
\n" ); document.write( ":
\n" ); document.write( "2y - z = 2
\n" ); document.write( "-y + z = 1
\n" ); document.write( "--------------addition eliminates z, find y
\n" ); document.write( "y = 3
\n" ); document.write( ":
\n" ); document.write( "Use the 3rd equation to find z:
\n" ); document.write( "3x -4y + 2z = -1
\n" ); document.write( "3(1) - 4(3) + 2z = -1
\n" ); document.write( "3 - 12 + 2z = -1
\n" ); document.write( "-9 + 2z = -1
\n" ); document.write( "2z = -1 + 9
\n" ); document.write( "2z = 8
\n" ); document.write( "z = 4
\n" ); document.write( ":
\n" ); document.write( ":
\n" ); document.write( "Check solutions in the 2nd equation; x = 1; y = 3; z = 4
\n" ); document.write( "2x - y + z = 3
\n" ); document.write( "2(1) - 3 + 4 = 3
\n" ); document.write( "2 - 3 + 4 = 3 \n" ); document.write( "
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