Question

How do you find the value of variables in a circle? Number 9?

Answer 1

a is half of the arc angle 108 so a = 54.
b is half of the arc angle 60 so b = 30.
c is identical to the angle that's missing from the triangle with a and b in it.
so, a + b + c = 180
54+60+c = 180
c = 180-54-60 = 66