WEBVTT

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Here is the problem: Solve the triangle with sides a equals 5, b equals 6, c equals 7.

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Side a is opposite angle A, b opposite B and c opposite C. This is the SSS case.

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Each angle from the law of cosines.

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Area and perimeter.

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So the answer is a equals 5, b equals 6, c equals 7; A equals 44.4153086°, B equals 57.12165044°, C equals 78.46304097°; area equals 14.69693846, perimeter equals 18.

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Three measurements including a side normally fix a triangle. Two sides with a non-included angle (SSA) can give zero, one or two triangles.

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Triangle 1: angles sum to 180°; a/sin A equals 7.144345083 equals c/sin C equals 7.144345083.