In Fig. 16.186, O is the centre of the circle. If ∠CEA=30°, find the values of x, y and z.
We have,
∠AEC = 30o
Since, quadrilateral ABCE is a cyclic quadrilateral
Then,
∠BAC + ∠AEC = 180o
x + 30o= 180o
x = 150o
By degree measure theorem,
∠AOC = 2 ∠AEC
y = 2 * 30o
= 60o
Therefore,
∠ADC = ∠AEC (Angles in same segment)
z = 30o