Section T6_1.
Context `{TnEQD:Tarski_neutral_dimensionless_with_decidable_point_equality}.
(** out reflexivity. l6_5 *)
(** out symmetry. *)
(** out transitivity. *)

Lemma l6_11_uniqueness : forall A B C R X Y,
Out A X R -> Cong A X B C ->
Out A Y R -> Cong A Y B C ->
X=Y.