If AB = QR, BC = PR and CA = PQ, then

∆PQR ≅ ∆BCA ∆ABC ≅ ∆PQR ∆CBA ≅ ∆PRQ ∆BAC ≅ ∆RPQ

∆CBA ≅ ∆PRQ

We are given that :- AB = QR, BC = PR and CA = PQ By side - side - side OR SSS congruency theorem, ∆CBA ≅ ∆PRQ