Question

The circumcentre of the triangle abc is o. Prove that ∠obc + ∠bac = 90o

Answer 1

OBC=OCB. (Opposite angles of equal Sides)

In triangle BOC,

BOC+OBC+OCB=180°

2OBC+2BAC=180°

2(OBC+BAC)=180°

OBC+BAC=90°

Hence Proved

Answer 2

Answer:

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