Answer:
Step-by-step explanation:
a) angle CAD= angle ODA ( in triangle OAD, OA=OD(same radius) angels opp to equal sides are equal)
hence angle CAD=42
b)angle b =90(angle subtended by diameter)
hence using angle sum property in triABC,
angle ACB=66-------------eq4
c) in tri OAD,
Angle AOD=180-(42+42)-------(using angle sum prop.)
=> 96-----------------eq1
angleACD=1/2 Angle AOD ( angle subtende by an arc at centre is double the angle subtended...)
hence angle ACD =1/2 x 96(from eq1)
angleACD=48--------------eq3
from eq 3,and eq4,
angle BCD= 48+66
=114 degree...
hope this helped you........pls mark brainliest