In a triangle ABC, angle A = 65° and angle B = 45°. Find the size of exterior angle at vertex C.
Answer and explanation
Correct answer: B. 110°
- Step 1: The exterior angle of a triangle equals the sum of the two opposite interior angles. Step 2. Exterior angle at C = angle A + angle B = 65° + 45° = 110°. Answer: 110°. Why not the others: 70° is the interior angle at C (180° - 110°); 100° and 120° are arithmetic calculation errors.
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