document.write( "Question 172008: find the inverse of matrix.
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Algebra.Com's Answer #128643 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "5-step rule for finding the inverse of a 2x2 matrix:\r\n" );
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document.write( "Step 1. Find the determinant by finding the difference\r\n" );
document.write( "between the product of the elements on the\r\n" );
document.write( "upper left to lower right diagonal, and the \r\n" );
document.write( "product of the elements on the upper left to \r\n" );
document.write( "lower right diagonal.  If this determinant is 0,\r\n" );
document.write( "then the matrix has no inverse and is said to\r\n" );
document.write( "be \"singular\".\r\n" );
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document.write( "Step 2. Swap the elements in the upper left to lower right\r\n" );
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document.write( "Step 3. Change the signs of the upper right to lower left\r\n" );
document.write( "diagonal elements.\r\n" );
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document.write( "Step 4. Divide every element by the determinant value\r\n" );
document.write( "fund in step 1.\r\n" );
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document.write( "Step 5. Reduce if possible.\r\n" );
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document.write( "Matrix 1. \"%28matrix%282%2C2%2C2%2C+-1%2C10%2C+7%29%29\"\r\n" );
document.write( "Step 1. Find the determinant by finding the difference\r\n" );
document.write( "between the product of the elements on the\r\n" );
document.write( "upper left to lower right diagonal, and the \r\n" );
document.write( "product of the elements on the upper left to \r\n" );
document.write( "lower right diagonal.   If this determinant is 0,\r\n" );
document.write( "then the matrix has no inverse and is said to\r\n" );
document.write( "be \"singular\".\r\n" );
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document.write( "\"determinant+=+%282%29%287%29-%28-1%29%2810%29+=+%2814%29-%28-10%29+=+14%2B10+=+24\"     \r\n" );
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document.write( "Step 2. Swap the elements in the upper left to lower right\r\n" );
document.write( "diagonal.\r\n" );
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document.write( "\"%28matrix%282%2C2%2C7%2C+-1%2C10%2C+2%29%29\"\r\n" );
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document.write( "Step 3. Change the signs of the upper right to lower left\r\n" );
document.write( "diagonal elements.\r\n" );
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document.write( "\"%28matrix%282%2C2%2C7%2C+1%2C-10%2C+2%29%29\"\r\n" );
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document.write( "Step 4. Divide every element by the determinant value\r\n" );
document.write( "fund in step 1.\r\n" );
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document.write( "\"%28matrix%282%2C2%2C7%2F24%2C+1%2F24%2C-10%2F24%2C+2%2F24%29%29\"\r\n" );
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document.write( "Step 5.  Reduce if possible\r\n" );
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document.write( "\"%28matrix%282%2C2%2C7%2F24%2C+1%2F24%2C-5%2F12%2C+1%2F12%29%29\"\r\n" );
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document.write( "You do the other two following this same \r\n" );
document.write( "5-step rule:\r\n" );
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document.write( "Matrix 2. \"%28matrix%282%2C2%2C-4%2C+2%2C-5%2C+1%29%29\" \r\n" );
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document.write( "answer: \"%28matrix%282%2C2%2C1%2F6%2C-1%2F3%2C5%2F6%2C-2%2F3%29%29\"\r\n" );
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document.write( "Matrix 3. \"%28matrix%282%2C2%2C9%2C+-3%2C-6%2C+2%29%29\"\r\n" );
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document.write( "answer: Singular matrix, has no inverse.\r\n" );
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document.write( "Edwin
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