Ex 9.1, 1 - Chapter 9 Class 9 Circles

Transcript

Ex 9.1, 1 Recall that two circles are congruent if they have the same radii. Prove that equal chords of congruent circles subtend equal angles at their centres. Given: Two congruent circles C1 & C2 AB is the chord of C1 & PQ is the chord of C2 AB = PQ To prove: Angle subtended by chords are equal i.e. AOB = PXQ Proof: In AOB & PXQ AO = PX BO = QX AB = PQ AOB PXQ AOB = PXQ