Question

please help me. complete it please​

Answer 1

Answer:

∠AOB = 180 -50 = 130  ( linear pair)

∠AOB = 130°

∠OAB = ∠OBA  are equal,since OB and OA are radii

hence ΔAOB  is isosceles.

∠OAB = ∠OBA = 25°

as ∠OAB + ∠OBA + ∠AOB = 180 ° (angle sum ppty of triangle)

2∠OAB + ∠AOB = 180°   (since  ∠OAB = ∠OBA )

2∠OAB + 130°  = 180°

2∠OAB = 50°

∠OAB =25°

∠OAC = 25°  (as how ∠OAB =25° )

∠BOC = ∠DOB + ∠DOC

100° = 50°  + 50°