document.write( "Question 843704: Perform the indicated row operations, then choose the new matrix.
\n" ); document.write( "[ 1 1 1 |-1]
\n" ); document.write( "[-1 2 1 |6] R1 + R2→R2;-2R1+R3→R3
\n" ); document.write( "[ 2 -1 3 |15]\r
\n" ); document.write( "\n" ); document.write( "A. 1 1 1/-1
\n" ); document.write( " 0 3 2/5
\n" ); document.write( " 0 -3 5/13\r
\n" ); document.write( "\n" ); document.write( "B. 1 1 1/-1
\n" ); document.write( " 0 3 2/5
\n" ); document.write( " 0 -3 1/17\r
\n" ); document.write( "\n" ); document.write( "C. 1 1 1/-1
\n" ); document.write( " 0 1 0/7
\n" ); document.write( " 0 -3 1/17\r
\n" ); document.write( "\n" ); document.write( "D. 1 1 1/-1
\n" ); document.write( " 0 1 0/7
\n" ); document.write( " 0 -3 5/13 \n" ); document.write( "
Algebra.Com's Answer #508328 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "[ 1  1 1 |-1]\r\n" );
document.write( "[-1  2 1 | 6] \r\n" );
document.write( "[ 2 -1 3 |15]\r\n" );
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document.write( "R1 + R2→R2  means to add row 1 and row 2 and take what you get and\r\n" );
document.write( "replace row 2 with it.\r\n" );
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document.write( "So we add row 1 and row 2\r\n" );
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document.write( "                     R1 = [  1  1 1 |-1]\r\n" );
document.write( "                   + R2 = [ -1  2 1 | 6]\r\n" );
document.write( "                    --------------------   \r\n" );
document.write( "                  R1+R2 = [  0  3 2 | 5]\r\n" );
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document.write( "Now we replace row 2 with that sum:\r\n" );
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document.write( "[1  1 1 |-1]\r\n" );
document.write( "[0  3 2 | 5]\r\n" );
document.write( "[2 -1 3 |15]\r\n" );
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document.write( "-2R1+R3→R3  means to multiply R1 by -2 and add it to row 3\r\n" );
document.write( "and take what you get and replace row 3 by it:\r\n" );
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document.write( "So we multiply row 1 by -2 \r\n" );
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document.write( "                     R1 = [  1  1  1 |-1]\r\n" );
document.write( "                                    ×(-2)\r\n" );
document.write( "                     -------------------\r\n" );
document.write( "                   -2R1 = [ -2 -2 -2 | 2]\r\n" );
document.write( "add to row 3-->      R3 = [  2 -1  3 |15] \r\n" );
document.write( "                     --------------------\r\n" );
document.write( "                 -2R+R3 = [  0 -3  1 |17]\r\n" );
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document.write( "Now we replace row 3 by that result:\r\n" );
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document.write( "[1  1 1 |-1]\r\n" );
document.write( "[0  3 2 | 5]\r\n" );
document.write( "[0 -3 1 |17]\r\n" );
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document.write( "Edwin
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