(***************************************************************************)
(* Formalization of the Chou, Gao and Zhang's decision procedure.          *)
(* Julien Narboux (Julien@narboux.fr)                                      *)
(* LIX/INRIA FUTURS 2004-2006                                              *)
(* University of Strasbourg 2008                                           *)
(***************************************************************************)
Require Export area_elimination_lemmas.

(* Specifications: *)
Theorem combine_inter_parallel : forall A B C E F X Y r,
(on_parallel_d X C A B r) ->
(inter_ll Y C X E F) ->
~ Col C A B ->
(on_inter_line_parallel Y C E F A B).