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

Lemma l14_36_a : forall O E E' A B C,
Sum O E E' A B C -> Out O A B -> Bet O A C.