WEBVTT

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Here is the problem: Solve the triangle with sides a equals 10, b equals 10, c equals 12.

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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 10, b equals 10, c equals 12; A equals 53.13010235°, B equals 53.13010235°, C equals 73.73979529°; area equals 48, perimeter equals 32.

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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 12.5 equals c/sin C equals 12.5.