In △ ABC, the opposite sides of ∠ a, B and C are a, B and C respectively, and a & # 178; + 2Ab = C & # 178; + 2BC. Try to judge the shape of △ ABC As mentioned above~

In △ ABC, the opposite sides of ∠ a, B and C are a, B and C respectively, and a & # 178; + 2Ab = C & # 178; + 2BC. Try to judge the shape of △ ABC As mentioned above~

a²+2ab=c²+2bc
a²-c²+2ab-2bc=0
(a+c)(a-c)+2b(a-c)=0
(a-c)(a+c+2b)=0
a-c=0
a=c
ABC is an isosceles triangle