# Math Help - A Symmtric Difference Question

1. ## A Symmtric Difference Question

I have to admit that I am completely lost on this one.

For any three sets $A, B, C,$ show that $A \bigtriangleup B = C$ if and only if $A=B \bigtriangleup C$.

2. Originally Posted by akolman
I have to admit that I am completely lost on this one.

For any three sets $A, B, C,$ show that $A \bigtriangleup B = C$ if and only if $A=B \bigtriangleup C$.