The sides AB and AC of ΔABC are produced up to points D and E. The bisectors of the exterior angles so formed, intersect each other at point I. If ∠ACB is 66° and ∠ABC = 44°, then what is the measure (in degrees) of ∠BIC ? |
52 50 48 55 |
55 |
We know that, The sum of the angles of the triangle = 180o ∠A = 180° - (44° + 66°) = ∠A = 70° ∠BIC = 90 - ∠A/2 (Exterior angle bisector) ∠BIC = 90 - 70/2 = 90 - 35 = 55° |