document.write( "Question 626982: solve 2x-y+z=-7, x-3y+4z=-19, and -x+4y-3z=18\r
\n" ); document.write( "\n" ); document.write( "can someone show how they got the answer please, ty \n" ); document.write( "
Algebra.Com's Answer #394565 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
solve
\n" ); document.write( "2x-y+z=-7
\n" ); document.write( "x-3y+4z=-19
\n" ); document.write( "-x+4y-3z=18
\n" ); document.write( "----------------
\n" ); document.write( "Rearrange the equations
\n" ); document.write( "x-3y+4z = -19
\n" ); document.write( "-x+4y-3z= 18
\n" ); document.write( "2x-y+z = -7
\n" ); document.write( "------
\n" ); document.write( "Add 1st to 2nd
\n" ); document.write( "Subtract 2 times 1 from 3rd to get:
\n" ); document.write( "x - 3y + 4z = -19
\n" ); document.write( "0 + y + z = -1
\n" ); document.write( "0 + 5y - 7z = 41
\n" ); document.write( "--------------------
\n" ); document.write( "Subtract 5 times 2nd from 3rd to get:
\n" ); document.write( "x - 3y + 4z = -19
\n" ); document.write( "0 + y + z = -1
\n" ); document.write( "0 + 0 - 12z = 36
\n" ); document.write( "---------------------
\n" ); document.write( "Solve the 3rd equation for \"z\":
\n" ); document.write( "z = -3
\n" ); document.write( "-----
\n" ); document.write( "Substitute z = -3 into the 2nd equation
\n" ); document.write( "and solve for \"y\":
\n" ); document.write( "y = 2
\n" ); document.write( "----
\n" ); document.write( "Substitute z = -3 and y = 2 into the 1st equation
\n" ); document.write( "and solve for \"x\":
\n" ); document.write( "x -3*2 + 4*-3 = -19
\n" ); document.write( "x -6 -12 = -19
\n" ); document.write( "x = -1
\n" ); document.write( "==========
\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
\n" ); document.write( "==========
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