Question

Two circles are congruent if their radii are -​

Answer 1

Answer:

two circles are congruent if they have the same radius then equal chords of congruent circles subtend equal angles at their centres.

Answer 2

Answer:

equal chords of congruent circles subtend equal angles at their centres

Step-by-step explanation:

Let us consider a circle with center O and two equal chords of a circle AB and CD.

We need to prove that ∠AOB=∠COD

In △ AOB and COD, we have

AO=CO (Radius of the circle)

BO=DO (Radius of the circle)

AB=CD (Equal chords)

By SAS criterion of congruence, we have

△AOB≅△COD

⇒∠AOB=∠COD

HOPE IT HELPS YOU..