Question

if in ∆ABC the bisector of angle B and angle C intersect each other at O. Prove that angle BOC=90°+1/2 angle A​

Answer 1

Answer:

Step-by-step explanation:

in triangle ABC, A +B+C=180     [angle sum property]

     therefore, A +2X +2Y=180

      THUS     , A/2 +X+Y=90                       [EQUATION 1]

now in triangle BOC, X+Y+O=180

                        BUT, X+Y=90-A/2

          THEREFORE, 90-A/2+O=180

                    THUS, BOC = 90+A/2