Question

solve this question please

Answer 1

<D +<B = 180 (ABCD is cyclic )

→<B = 60.

Now , < in a semi circle is 90.

→ <ACB = 90.

By angle sum property of a∆ we get ,

x = 180-90-60

→x = 30

Answer 2

as we know it's a cyclic quadrilateral

ADC=120

ABC=60

AOB = 180

ACB=90(THEOREM10.1)

90+60+X=180(ANGLE SUM PROPERTY)

X=180-150

30