document.write( "Question 1201128: Pivot the system about the element in row 1, column 1. (Enter the augmented matrix with all cells in their original position.)\r
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Algebra.Com's Answer #835569 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "The element to pivot on is called 'the pivot element'.\r\n" );
document.write( "The pivot element's row is called 'the pivot row'.\r\n" );
document.write( "The pivot element's column is called 'the pivot column'.\r\n" );
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document.write( "To pivot on an element, \r\n" );
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document.write( "Step 1. if the pivot element is not already 1, we divide the pivot row through\r\n" );
document.write( "by itself to make the pivot element become 1. \r\n" );
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document.write( "then \r\n" );
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document.write( "Step 2. We use that 1 to cause every other element in the pivot column to\r\n" );
document.write( "become 0.\r\n" );
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document.write( "We can skip Step 1 because the pivot element is already 1.  \r\n" );
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document.write( "So we go on to Step 2:\r\n" );
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document.write( "Out to the side or on scratch paper, we write down the pivot row \r\n" );
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document.write( "        1 3 | 4 \r\n" );
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document.write( "Multiply it through by -3 because -3 is what is needed to add to the 3 under the\r\n" );
document.write( "pivot element to make it become 0.  When we multiply the pivot row by -3, we\r\n" );
document.write( "get:\r\n" );
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document.write( "      -3 -9 | -12\r\n" );
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document.write( "Then we write the second row under it and add:\r\n" );
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document.write( "      -3 -9 | -12\r\n" );
document.write( "       3  6 |   9\r\n" );
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document.write( "       0 -3 |  -3\r\n" );
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document.write( "Then we write that in place of the second row:\r\n" );
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document.write( "That completes the pivoting on the first element in the first row, first column.\r\n" );
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document.write( "The idea is to make the pivot element become 1 and then use it to make all the\r\n" );
document.write( "other elements in the pivot column become 0's.\r\n" );
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document.write( "Edwin

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