(* Gabriel Braun April 2013 *)
Require Export GeoCoq.Tarski_dev.Ch13_2_length.
Section Angles_1.
Context `{TnEQD:Tarski_neutral_dimensionless_with_decidable_point_equality}.
(************************************* angle *****************************)

(* Specifications: *)
Lemma ang_exists : forall A B C, A <> B -> C <> B -> exists a, Q_CongA a /\ a A B C.
Lemma ex_points_ang : forall a , Q_CongA a ->  exists A, exists B, exists C, a A B C.
End Angles_1.