Section CONGRUENT_STRICT_TRIANGLES.
Definition CongruentStrictTriangles (A B C A' B' C' : Point) :=
CongruentTriangles A B C A' B' C' /\
~Collinear A B C.

Lemma EquiDirectedCollinear : forall A B C : Point,
EquiDirected A B B C ->
Collinear A B C.