Question

P and Q are centres of the two intersecting circles which intersect at R prove that PQ =QR= PR

Answer 1

by theorem of two circles are touching circles then the common point lies in the line joining their centers

Answer 2

in a circle having centre P, we have
                      PR=PQ---------------------------------1st equation
in a circle having centre Q, we have
                     QR=QP----------------------------------2nd equation
 from equation 1 and 2, we get
  PR=PQ=QR
 



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