document.write( "Question 719021: \"Solve the system of linear equations, using row echelon form.\"
\n" ); document.write( "Eq 1. 2x + 2z = 2
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\n" ); document.write( "\n" ); document.write( "I am getting different answers everytime, while the book says the answers are (-4,8,5). \r
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Algebra.Com's Answer #441164 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Eq 1. 2x + 2z = 2\r\n" );
document.write( "Eq 2. 5x + 3y = 4\r\n" );
document.write( "Eq 3. 3y - 4z = 4 \r\n" );
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document.write( "Line them up:\r\n" );
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document.write( "2x      + 2z = 2\r\n" );
document.write( "5x + 3y      = 4\r\n" );
document.write( "     3y - 4z = 4\r\n" );
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document.write( "2x + 0y + 2z = 2\r\n" );
document.write( "5x + 3y + 0z = 4\r\n" );
document.write( "0x + 3y - 4z = 4\r\n" );
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document.write( "Multiply the first row thru by \"1%2F2\",\r\n" );
document.write( "abbreviated:  \"1%2F2\"R1->R1\r\n" );
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document.write( "Multiply the first row through by -5, add to\r\n" );
document.write( "the second row, then restore the first row,\r\n" );
document.write( "abbreviated   -5R1+R2->R2\r\n" );
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document.write( "Multiply the second row through by -1, add to\r\n" );
document.write( "the third row, then restore the second row,\r\n" );
document.write( "abbreviated   -R2+R3->R3 \r\n" );
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document.write( "Convert back to equations:\r\n" );
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document.write( "1x + 0y + 1z =  1\r\n" );
document.write( "0x + 3y - 5z = -1\r\n" );
document.write( "0x + 0y + 1z =  5\r\n" );
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document.write( "x + z =  1\r\n" );
document.write( "3y - 5z = -1\r\n" );
document.write( "z = 5\r\n" );
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document.write( "Substitute z = 5 into \r\n" );
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document.write( "3y - 5z   = -1\r\n" );
document.write( "3y - 5(5) = -1\r\n" );
document.write( "  3y - 25 = -1\r\n" );
document.write( "       3y = 24\r\n" );
document.write( "        y = 8\r\n" );
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document.write( "Substitute z = 5 into\r\n" );
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document.write( "x + z = 1\r\n" );
document.write( "x + 5 = 1\r\n" );
document.write( "    x = -4\r\n" );
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document.write( "Edwin
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