$\"\"$

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The lengths are $\"\"$ , $\"\"$ and $\"\"$ .

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Herons formula :

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The area of $\"\"$ is $\"\"$ .

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Where $\"\"$ .

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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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Therefore the area of triangle is $\"\"$ .

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$\"\"$

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The area of triangle is $\"\"$ .