$\"\"$

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From the given data : $\"\"$ , b = 6 and c = 7.

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Law of cosines for cos A : $\"\"$ .

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$\"\"$ (Substitute : $\"\"$ , b = 6 and c = 7)

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$\"\"$ (Simplify)

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$\"\"$ ( $\"\"$ )

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$\"\"$ (Simplify)

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$\"\"$ (Take square root each side)

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$\"\"$ (Simplify) $\"\"$

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Law of cosines for cos B : $\"\"$ .

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$\"\"$ (Substitute : a = 11.26, b = 6 and c = 7)

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$\"\"$ (Simplify)

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$\"\"$

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$\"\"$ (Simplify)

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$\"\"$ ( $\"\"$ ) $\"\"$

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Law of cosines for cos C : $\"\"$ .

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$\"\"$ (Substitute : a = 11.26, b = 6 and c = 7)

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$\"\"$ (Simplify)

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$\"\"$

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$\"\"$ (Simplify)

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$\"\"$ ( $\"\"$ ) $\"\"$

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The solution is $\"\"$ , $\"\"$ and $\"\"$ .