Question

Pls answer this question​

Answer 1

Answer:

AOB is diameter

OA =OB

angle COB = 180-100 = 80

angle CDB = 1÷2 × 80

= 40

Answer 2

Answer:

Angle COB= 180°- angle AOC

hence, angle COB =80°

arc CB=angle COB=80° -measure of central angle

Angle CDB= 1/2× arc CB

1/2×80°=40°

hence angle CDB is 40°