Question

in the given figure O is the centre of a circle if angle ADB is equal to 50 degree and COD is a straight line then the measure of angle Coa is

Answer 1

the one more angle is 130 degree

Answer 2

Answer:

Step-by-step explanation:

By degree measure theorem,

reflex∠AOC=2∠CBA

  360°-100°=2∠CBA

          260°=2∠CBA

      260°÷2=∠CBA

∴∠CBA=130°

AD is a line.

∴∠CBA+∠CBD=180°                     (Linear pair)

 ⇒130°+∠CBD=180°

             ∠CBD=180°-130°=50°

∴∠CBD=50°