# ABC is a triangle in which ∠A = 72°, the internal bisectors of angles B and C meet in O. Find the magnitude of ∠BOC.

Given,

ABC is a triangle

A = 72o and internal bisectors of B and C meet O.

In

A + B + C = 180o

72o + B + C = 180o

B + C = 180o – 72o

B + C = 108o

Divide both sides by 2, we get

+ =

+ = 54o

OBC + OCB = 54o (i)

Now, in

OBC + OCB + BOC = 180o

54o + BOC = 180o [Using (i)]

BOC = 180o – 54o

= 126o

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Quiz | Angle Sum Property of Triangle40 mins
Quiz | Lines and Angles43 mins
Quiz | Lines and Angles40 mins
NCERT | Angle Sum Property44 mins
Matter and Its Classification34 mins
Lines and Angles45 mins
NCERT | Intersecting and Non Intersecting lines)41 mins
NCERT | Discussion on Lines And Angles45 mins
Know About Transversal and Parallel lines42 mins
Champ Quiz | Triangle Inequality27 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
view all courses