Hint Resolve equilateral_strict_swap_1 equilateral_strict_swap_2
equilateral_strict_swap_3 equilateral_strict_swap_4 equilateral_strict_swap_5 : equilateral.

(* Specifications: *)
Lemma equilateral_strict__not_col :
equilateral_strict A B C -> ~ Col A B C.
Lemma equilateral_strict_conga_1 :
equilateral_strict A B C ->
CongA C A B A C B.