document.write( "Question 343991: Solve by the Gauss-Jordan elimination: \r
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Algebra.Com's Answer #246093 by Edwin McCravy(20054)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Put in all the 1 coefficients\r\n" );
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document.write( "Take out the variables and replace the column\r\n" );
document.write( "of equal signs by a vertical line:\r\n" );
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document.write( "Do row operations\r\n" );
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document.write( "-1R1+R2->R2\r\n" );
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document.write( "(That means to multiply row 1 temporarily by -1\r\n" );
document.write( "and add it to row 2, replace row 2 by that, then\r\n" );
document.write( "restore row 1 as it was):\r\n" );
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document.write( "-2R1+R3->R3\r\n" );
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document.write( "-R1+R4->R4\r\n" );
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document.write( "-R2+R1->R1\r\n" );
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document.write( "R2+R3->R3\r\n" );
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document.write( "R3->R4\r\n" );
document.write( "R4->R3\r\n" );
document.write( "(That means to interchange row 3 and row 4)\r\n" );
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document.write( "-R3->R3\r\n" );
document.write( "{That means to multiply row 3 by -1)\r\n" );
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document.write( "-3R3+R1->R1\r\n" );
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document.write( "R3+R2->R2\r\n" );
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document.write( "4R3+R4->R4\r\n" );
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document.write( "\"-1%2F5\"R4->R4\r\n" );
document.write( "(That means to multiply row 4 by \"1%2F5\")\r\n" );
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document.write( "-4R4+R1->R1\r\n" );
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document.write( "R4+R2->R2\r\n" );
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document.write( "-R4+R3->R3\r\n" );
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document.write( "Place the variables and equal signs back in\r\n" );
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document.write( "Simplify:\r\n" );
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document.write( "\"system%28x=2%2C%0D%0Ay=0%2C%0D%0Az=-1%2C%0D%0At=1%29\"\r\n" );
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document.write( "Edwin
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