(* Gabriel Braun April 2013 *)
Require Export GeoCoq.Tarski_dev.Ch13_4_cos.
Require Export GeoCoq.Tarski_dev.Annexes.project.
Section Pappus_Pascal.
Context `{T2D:Tarski_2D}.
Context `{TE:@Tarski_euclidean Tn TnEQD}.

Lemma l13_6_bis : forall lp l1 l2 a, Lcos lp l1 a -> Lcos lp l2 a -> EqL l1 l2.