$\"\"$

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Observe the matrix; the matrix has 3 rows and 3 columns.

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So, the dimensions of matrix are $\"\"$ .

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The determinant of a $\"\"$ matrix is called third-order determinant.

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Evaluate the third-order determinant using expansion by minors method $\"\"$ $\"\"$

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Find the determinant using third-order determinant definition.

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Slove det $\"\"$

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$\"\"$ $\"\"$

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Evaluate the $\"\"$ determinants using second-order determinant definition.

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$\"\"$

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$\"\"$

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$\"\"$

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Product of two same sings is positive.

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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Rewrite the equation $\"\"$

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Take out common factors.

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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Subtract 4 from each side. \ \

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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Divide each side by 3.

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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Add 2 to each side.

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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The value of $\"\"$ .