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

Theorem elim_py_on_line_right :
forall A B P Q Y : Point,
on_line Y P Q ->
Py A B Y = P ** Y / P ** Q * Py A B Q + (1 - P ** Y / P ** Q) * Py A B P.