How to break the Y outline here?

Hello guys, I know you guys are all experts, this answer probably can be found somewhere online but I tried… I really did…

I have this Y shape outline, and I am trying to break one of its arms.

So from connected arm:

To dislocated arm like this:

I used the dumbest method, drew a white stroke to break it. Obviously it’s a kid’s move…

Thank you in advance.