Triangle ABC has an exterior angle at vertex C. The interior angle at A is 48° and the interior angle at B is 67°. What is the size of the exterior angle at C?

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Question

Triangle ABC has an exterior angle at vertex C. The interior angle at A is 48° and the interior angle at B is 67°. What is the size of the exterior angle at C?

Accepted Answer

115° — Award 1 mark for applying the exterior angle theorem: exterior angle = sum of two opposite interior angles = 48° + 67° = 115°. A is incorrect — this is the interior angle at C (180° − 115° = 65°). C is incorrect — this is the angle sum of a triangle. D is incorrect — this adds all three values incorrectly.

Answer

65°

Answer

115°

Answer

180°

Answer

245°

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