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

Lemma segment_construction_3 : forall A B X Y, A <> B -> X <> Y -> exists C, Out A B C /\ Cong A C X Y.