$\"\"$

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The parametric equations are $\"\"$ and $\"\"$ .

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Eliminate parameter $\"\"$ .

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Consider $\"\"$ .

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$\"\"$

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$\"\"$ .

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Substitute $\"\"$ in $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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The rectangular equation is $\"\"$ .

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$\"\"$

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The rectangular equation is $\"\"$ .