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

Lemma l4_2 : forall A B C D A' B' C' D', IFSC A B C D A' B' C' D' -> Cong B D B' D'.