Q28 of 100 Page 17

In Fig. 16.204, if ∠ABC= 45°, then ∠AOC=

We know that,

An angle subtended by an arc at the centre of the circle is double the angle subtended at any point on the circle

∠AOC = 2 ∠ABC

= 2 * 45°

= 90°

In Fig. 16.202, O is the centre of the circle such that ∠AOC=130°, then ∠ABC=

In Fig. 16.203, if chords AB and CD of the circle intersect each other at right angles, then x + y =

In Fig. 16.205, chords AD and BC intersect each other at right angles at a point P. If ∠DAB=35°, then ∠ADC=

In Fig. 16.206, O is the centre of the circle and ∠BDC=42°. The measure of ∠ACB is