Question

In given figure , O is the centre of the circle. If abc is 160° find the value of x

Answer 1

x = 100° hope it helps you
because 160/2=80°

then 80°+x = 180°
x = 100°

Answer 2

hey!

theorems to be known

angle subtended at the centre is twice the angle subtended at remaining part of the circle

NOTE - sum of opposite angles of a cyclic quadrilateral is 180°

1/2<AOC= <ADC
1/2×160°=80° = <ADC

ABCD is a cyclic quadrilateral

<D+<B =180°
<B = 180°-80°
<B=100°
x=100°