document.write( "Question 307509: Perform an operation on the given system that eliminates the indicated variable and solve for the unknown variables.
\n" ); document.write( "x-4y+z=3
\n" ); document.write( " y-3z=10
\n" ); document.write( " 3y-8z=24 \n" ); document.write( "
Algebra.Com's Answer #219996 by rapaljer(4671)\"\" \"About 
You can put this solution on YOUR website!
Multiply the second equation by -3 and add to the third equation.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "-3y+9z=-30
\n" ); document.write( "3y-8z=24
\n" ); document.write( "z=-6\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Now, substitute z=-6 into the second equation:
\n" ); document.write( "y-3x=10
\n" ); document.write( "y-3*-6=10
\n" ); document.write( "y+18=10
\n" ); document.write( "y=-8\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Finally, substitute both z and y into the first equation:
\n" ); document.write( "x-4y+z=3
\n" ); document.write( "x-4(-8)+-6=3
\n" ); document.write( "x+32-6=3
\n" ); document.write( "x=3+6-32=-23\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "I used a program in my TI84 called \"POLYSIMULT\" to check this answer. If you are interested in this, send me an Email at rapaljer@seminolestate.edu.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Dr. Robert J. Rapalje, Retired
\n" ); document.write( " \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "
\n" );