Question

In the figure given below, if O is the centre and BOA = 130°, then find the value of x.

Answer 1

Answer:

∠ADC=

2

1

∠AOC

(Angle subtended by a chord on mayor area is half of that subtended on center)

∴∠ADC=

2

1

×130=65

∘

Now, ADCB is cyclic quadrilateral ⇒

Sum of opposite Angles is 180

∘

∴∠ABC+∠ADC=180

∘

∠ABC+65=180

∘

∠ABC=115

∘