Question

In a triangleABC, if angleA = 60° and the bisectors of angleB and angleC meet AC and AB at P and Q respectively and
intersect each other at I, then angelBIC = :
(B) 75
(C) 120°
(D) 135°
(A) 90°​

Answer 1

Answer:

${120}^{o}$

Step-by-step explanation:

Using the property that three angles of a triangle equal to 180 degrees:

60+B+C=180

Now, B+C = 120

Dividing both sides by two:

B/2+C/2=60

In triangle BIC:

Using three angles equal 180 we get

B/2+C/2+I=180

Substituting B/2+C/2 in this we get:

I = 120 degrees