From the circumcentre I of the triangle ABC, perpendicular

Home » Aptitude » Plane Geometry » Question

From the circumcentre I of the triangle ABC, perpendicular ID is drawn on BC. If ∠BAC = 60°, then the value of ∠BID is :

1. 60°
2. 80°
3. 75°
4. 45°

Correct Option: A

As per the given in question , we draw a figure of a triangle ABC

Here , ∠BAC = 60°
BI = IC = in–radius
∴ Angle subtended by arc AC at the centre = 2 × ∠BAC
Angle subtended by arc AC at the centre = 2 × 60° = 120°

∴ ∠BID = ∠DIC =	120°	= 60°
	2