document.write( "Question 906682: 4x - y= 2
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Algebra.Com's Answer #550005 by Edwin McCravy(20060)\"\" \"About 
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document.write( "(1)    4x - y = 2\r\n" );
document.write( "(2)    3y + z = 9\r\n" );
document.write( "(3)    x + 2z = 7\r\n" );
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document.write( "z is already eliminated in (1),\r\n" );
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document.write( "so eliminate z from (2) and (3)\r\n" );
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document.write( "Solve (2) for z\r\n" );
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document.write( "(2)    3y + z = 9\r\n" );
document.write( "            z = 9 - 3y\r\n" );
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document.write( "Substitute 9-3y for z in (3)\r\n" );
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document.write( "(3)    x + 2z = 7\r\n" );
document.write( "  x + 2(9-3y) = 7\r\n" );
document.write( "  x + 18 - 6y = 7\r\n" );
document.write( "(4)    x - 6y = -11\r\n" );
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document.write( "Solve the system:\r\n" );
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document.write( "(1)    4x -  y = 2\r\n" );
document.write( "(4)     x - 6y = -11\r\n" );
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document.write( "Solve (4) for x\r\n" );
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document.write( "             x = -11+6y\r\n" );
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document.write( "Substitute -11+6y for x in (1)\r\n" );
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document.write( " 4(-11+6y) - y = 2    \r\n" );
document.write( "   -44+24y - y = 2 \r\n" );
document.write( "           23y = 46\r\n" );
document.write( "             y = 2\r\n" );
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document.write( "             x = -11+6y\r\n" );
document.write( "             x = -11+6(2)\r\n" );
document.write( "             x = -11+12\r\n" );
document.write( "             x = 1 \r\n" );
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document.write( "Substitute in            \r\n" );
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document.write( "             z = 9 - 3y\r\n" );
document.write( "             z = 9 - 3(2)\r\n" );
document.write( "             z = 9 - 6\r\n" );
document.write( "             z = 3\r\n" );
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document.write( "(x,y,z) = (1,2,3)\r\n" );
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document.write( "Edwin
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