∵,∠B=∠B1,∠C=∠C1
∴,∠A=∠A1
∴△ABC∽△A1B1C1
故BC/AB=B1C1/A1B1
又∵AB+BC=A1B1+B1C1
∴1+BC/AB=A1B1/AB+B1C1/AB
1+BC/AB=(1+B1C1/A1B1)×(A1B1/AB)
由BC/AB=B1C1/A1B1
得1+BC/AB=(1+BC/AB)×(A1B1/AB)
∴A1B1/AB=1
AB=A1B1
∴:△ABC≌△A1B1C1 (两角夹一边)
∵,∠B=∠B1,∠C=∠C1
∴,∠A=∠A1
∴△ABC∽△A1B1C1
故BC/AB=B1C1/A1B1
又∵AB+BC=A1B1+B1C1
∴1+BC/AB=A1B1/AB+B1C1/AB
1+BC/AB=(1+B1C1/A1B1)×(A1B1/AB)
由BC/AB=B1C1/A1B1
得1+BC/AB=(1+BC/AB)×(A1B1/AB)
∴A1B1/AB=1
AB=A1B1
∴:△ABC≌△A1B1C1 (两角夹一边)