Require Export GeoCoq.Tarski_dev.Ch03_bet.
Section T3.
Context `{TnEQD:Tarski_neutral_dimensionless_with_decidable_point_equality}.

Lemma l4_5 : forall A B C A' C',
Bet A B C -> Cong A C A' C' ->
exists B', Bet A' B' C' /\ Cong_3 A B C A' B' C'.