Q28 of 93 Page 10

In Fig. 10.65, common tangents PQ and RS to two circles intersect at A. Prove that PQ = RS.


Given: PQ and RS are the two common tangent to the two circle


To Proof: A is the point of intersection of PQ and RS


We know that , length of two tangent drawn from an exterior point to acirclr are equal.


Therefore


PA = RA----------------- (i)


QA = SA ------------------- (ii)


Adding two equations we get


PA + QA =RA + SA


PQ =RS (proved)


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