Question

In the figure. O is the centre of a circle passing through points A B C and D
and angle ADC = 120" Find the value of x
120​

Answer 1

Answer:

ABCD is a cyclic quadrilateral. we have

∠ABC+∠ADC=180

o

∠ABC=180

o

−120

o

=60

o

Also ∠ACB=90

o

( angle on a semi circle )

In ΔABC we have

∠BAC+∠ACB+∠ABC=180

o

∠BAC+90

o

+60

o

=180

o

∠BAC=180

o

−150

o

=30

o