WEBVTT

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Here is the problem: Solve the triangle with sides a equals 8, b equals 15, c equals 17.

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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 8, b equals 15, c equals 17; A equals 28.07248694°, B equals 61.92751306°, C equals 90°; area equals 60, perimeter equals 40.

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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 17 equals c/sin C equals 17.