- A70°
- B125°
- C110°
- D35°
Step-by-Step Solution
(180° − ∠B) + (180° − ∠C) = 250° gives ∠B + ∠C = 110°, so ∠A = 180° − 110° = 70°.
Answer: A) 70°
The exterior angles at B and C of △ABC add up to 250°. Find ∠A.
Class 9Exterior Angle of a TriangleGeometry — Lines and Angles
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