How do you diagram this?

LSAT Determined

I've been reading the LSAT trainer and am a little confused about the diagramming of the bi-conditional.

One question was: L will go before J if and only if L is after G. I diagrammed this as follows: L--J <----> G---L--J. However, the answer sheet has two different answers This:: L--J <----> G---L--J. and this: J---L---G. I don't understand the later. Is this supposed to be the contropsoitive or something?

MrSamIam

I believe those are the two possible "worlds" that you can be in. If L is before J, then G is before L and L is before J, and vice versa. If J is before L and L is before G, then J --- L --- G. In a nutshell, if neither of the conditions in the bi-conditional are met, then the only other possibility is J -- L -- G.
Try this: Ask yourself, what would happen if neither of the bi-conditional's conditions are present? Did you get J -- L -- G?

LSAT Determined

Thanks. That makes sense. I finally got it, I think