In a triangle ABC, ∠A = 70°, ∠B = 80° and D is

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In a triangle ABC, ∠A = 70°, ∠B = 80° and D is the incentre of ∆ ABC. ∠ACB = 2x° and ∠BDC = y°. The values of x and y, respectively are

1. 15, 130
2. 15, 125
3. 35, 40
4. 30, 150

Correct Option: B

As per the given in question , we draw a figure triangle ABC whose D is the incentre ,

The point of intersection of internal bisectors of angles of a triangle is in-centre.
∠A = 70°; ∠B = 80°
∴ ∠C = 180° – (70° + 80°) = 30°
∴ ∠ACB = 2x° = 30° ⇒ x = 15°

∠BDC = 180° -	∠B	-	∠C
	2		2

∠BDC = 180° -	80°	-	30°
	2		2

∠BDC = 180° – 40° – 15° = 125° = y