- A80°
- B30°
- C50°
- D100°
Step-by-Step Solution
∠ACD = ∠A + ∠B gives 2∠A = ∠A + 50°, so ∠A = 50° and ∠ACD = 100°. Then ∠ACB = 180° − 100° = 80°.
Answer: A) 80°
Side BC of △ABC is produced to D. ∠ACD = 2∠A and ∠B = 50°. Find the interior angle ∠ACB.
Class 9Exterior Angle of a TriangleGeometry — Lines and Angles
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