document.write( "Question 710737: Solve the matrix equation:
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Algebra.Com's Answer #437180 by Edwin McCravy(20056) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "This is really the matrix abbreviation for the system of equtions:  \r\n" );
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document.write( "Now we need to find the inverse of the coefficient matrix\r\n" );
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document.write( "To find the inverse of a 2x2 matrix:\r\n" );
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document.write( "1. Interchange the upper left and lower right elements:\r\n" );
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document.write( "2. Multiply the upper right and lower left elements by -1:\r\n" );
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document.write( "3. Find the determinant of this matrix:\r\n" );
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document.write( "4. Divide every element of  by this value:\r\n" );
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document.write( "That is the inverse of the coefficient matrix.\r\n" );
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document.write( "Left-multiply both sides of the matrix\r\n" );
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document.write( "by the inverse of the coefficient matrix:\r\n" );
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document.write( "Since matrix multiplication is associative, we can move\r\n" );
document.write( "the parentheses from around the 2nd and 3rd matrices\r\n" );
document.write( "on the left to around the 1st and 2nd matrices on the\r\n" );
document.write( "left:\r\n" );
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document.write( "Now we multiply the two matrices on the far\r\n" );
document.write( "left and the far right:  \r\n" );
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document.write( "Simplify:\r\n" );
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document.write( "Multiply the matrices on the left:\r\n" );
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document.write( "Simplify:\r\n" );
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document.write( "So the solution is \r\n" );
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document.write( "Edwin

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