proposition: Lemma prop_29_1 : forall A D G H, TS G H A D -> Par G A H D -> CongA A G H D H G.
proof: Proof. intros A D G H. apply l12_21_a. Qed.
imports: GeoCoq.Meta_theory.Continuity.elementary_continuity_props GeoCoq.Tarski_dev.Ch16_coordinates_with_functions