If ABCD is a cyclic quadrilateral with ∠A = 50°, ∠B

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If ABCD is a cyclic quadrilateral with ∠A = 50°, ∠B = 80°, then ∠C and ∠D are

1. 100°, 130°
2. 115°, 115°
3. 110°, 120°
4. 130°, 100°

Correct Option: D

In a concyclic quadrilateral ABCD,
We know that , The sum of opposite angles of a concyclic quadrilateral is 180
∠A + ∠C = 180°
⇒ 50° + ∠C = 180°
⇒ ∠C = 180° – 50° = 130°
Again,
∠B + ∠D = 180°
⇒ 80° + ∠D = 180°
⇒ ∠D = 180° – 80° = 100°