Require Export GeoCoq.Tarski_dev.Ch14_prod.
Section Order.
Context `{T2D:Tarski_2D}.
Context `{TE:@Tarski_euclidean Tn TnEQD}.

Lemma ltP_ar2 : forall O E E' A B, LtP O E E' A B -> Ar2 O E E' A B A.