\"\"

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Definition of rotation of axes:

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The general second-degree equation \"\" can be

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written as \"\" by rotating the axes by an angle \"\",

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where \"\", \"\" and \"\".

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\"\"

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The equation is \"\".

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Compare the equation \"\" with general equation.

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The values of  \"\", and \"\".

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\"\"

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\"\"

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Substitute \"\" in \"\" and \"\".

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Consider \"\".

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\"\"

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Consider \"\".

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\"\"

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Substitute \"\" and  \"\" in the equation \"\".

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\"\"

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The rotated equation is \"\".\"\"

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Graph :

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(1) Draw the coordinate plane.

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(2) Draw the rotated coordinate plane.

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(3) Graph the equation \"\".

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\"image\"

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\"\"

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The rotated equation is \"\".

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Graph of equation \"\" with rotated axis.

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\"image\"