Require Export GeoCoq.Elements.OriginalProofs.lemma_NChelper.
Require Export GeoCoq.Elements.OriginalProofs.proposition_16.
Require Export GeoCoq.Elements.OriginalProofs.lemma_crossbar.
Require Export GeoCoq.Elements.OriginalProofs.lemma_NCdistinct.
Require Export GeoCoq.Elements.OriginalProofs.lemma_NCorder.
Section Euclid.
Context `{Ax:euclidean_neutral_ruler_compass}.

(* Specifications: *)
Lemma proposition_17 :
forall A B C,
Triangle A B C ->
exists X Y Z, SumA A B C B C A X Y Z.