Section Archimedes_for_angles.
Context `{TnEQD:Tarski_neutral_dimensionless_with_decidable_point_equality}.

Lemma conga2_grada__grada : forall A B C D E F A' B' C' D' E' F',
GradA A B C D E F ->
CongA A B C A' B' C' -> CongA D E F D' E' F' ->
GradA A' B' C' D' E' F'.