proposition: Lemma proposition_15b : forall A B C D E : Point, BetS A E B -> BetS C E D -> nCol A E C -> CongA C E B A E D.
proof: Proof. intros. apply (proposition_15 A B C D E);assumption. Qed.
imports: GeoCoq.Elements.OriginalProofs.lemma_ABCequalsCBA GeoCoq.Elements.OriginalProofs.lemma_supplements GeoCoq.Elements.OriginalProofs.lemma_equalanglestransitive