document.write( "Question 255959: Find the inverse for the given matrix \r
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\n" ); document.write( "\n" ); document.write( "Then A^-1=\r
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Algebra.Com's Answer #188153 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Augment it with the identity matrix:\r\n" );
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document.write( "The idea is to make the left side become the\r\n" );
document.write( "identity matrix, and then the right side\r\n" );
document.write( "will become the inverse:\r\n" );
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document.write( "Multiply Row 2 by -4:\r\n" );
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document.write( "Add Row 1 to Row 2\r\n" );
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document.write( "Multiply Row 3 by -1\r\n" );
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document.write( "Add Row 1 to Row 3:\r\n" );
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document.write( "Multiply Row 4 by -4\r\n" );
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document.write( "Add Row 1 to Row 4\r\n" );
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document.write( "Multiply  Row 3 by -2\r\n" );
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document.write( "Add Row 2 to Row 3:\r\n" );
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document.write( "Multiply Row 2 by 9, and multiply Row 4 by 2\r\n" );
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document.write( "Add Row 2 to Row 4:\r\n" );
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document.write( "Multiply Row 3 by -1:\r\n" );
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document.write( "Add Row 3 to Row 4\r\n" );
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document.write( "Now divide the Row 1 through by -4,\r\n" );
document.write( "divide Row 2 through by -72,\r\n" );
document.write( "divide Row 3 through by -8\r\n" );
document.write( "divide Row 4 through by -8\r\n" );
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document.write( "Now we have the identity on the left, so the inverse is \r\n" );
document.write( "the 4x4 matrix on the right, that is:\r\n" );
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document.write( "Edwin

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