Require Export GeoCoq.Elements.OriginalProofs.lemma_parallelNC.
Require Export GeoCoq.Elements.OriginalProofs.lemma_parallelsymmetric.
Require Export GeoCoq.Elements.OriginalProofs.proposition_29B.
Require Export GeoCoq.Elements.OriginalProofs.lemma_NCdistinct.
Require Export GeoCoq.Elements.OriginalProofs.lemma_samesidetransitive.
Section Euclid.
Context `{Ax:euclidean_euclidean}.

Lemma lemma_Playfairhelper :
forall A B C D E,
Par A B C D -> Par A B C E -> CR A D B C -> CR A E B C ->
Col C D E.