Proving Symmetric Difference of A and B Let A and B be sets. Define the symmetric difference of A and B as A∆B= (A ∪ B) − (A ∩ B).
(a) Prove that A∆B = (A − B) ∪ (B − A)
I tried to start this but am getting really lost. if someone could try to help that would be great 

Hint:
If $x \in A\Delta B$, then x is an element that’s in A or B, but not both. Compare this to $(A - B)\cup(B-A)$. Would $x$ be in this set as well?
