document.write( "Question 364823: Solve for X ( 2x2 matrix ) \r
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Algebra.Com's Answer #260112 by Edwin McCravy(20086) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "Get terms in matrix X on the left and other matrix terms on the right:\r\n" );
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document.write( "Factor X out on the right\r\n" );
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document.write( "Subtract the two matrices in parentheses:\r\n" );
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document.write( "Simplify\r\n" );
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document.write( "Now we must find the inverse of the 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. Calculate the determinant by the rule:\r\n" );
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document.write( "upper left element times lower right element minus\r\n" );
document.write( "upper right element times lower left element\r\n" );
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document.write( "2. Exchange the upper left and lower right elements.\r\n" );
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document.write( "3. Change the signs of the upper right and lower left elements.\r\n" );
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document.write( "4. Divide each element by the value of the determinant found\r\n" );
document.write( "   in step 1.\r\n" );
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document.write( "Find the determinant of \r\n" );
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document.write( "1. (4)(-1)-(6)(7) = -4-42=-46\r\n" );
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document.write( "2. \r\n" );
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document.write( "3. \r\n" );
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document.write( "4. , simplifying,\r\n" );
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document.write( "Now take the equation\r\n" );
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document.write( "and left-multiply both sides by this inverse matrix:\r\n" );
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document.write( "Do the matrix multiplication.  I assume you know how. If not post again,\r\n" );
document.write( "asking how.\r\n" );
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document.write( "Edwin

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