Section Circumcenter2 .
Context `{TE:Tarski_euclidean}.
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Lemma circumcenter_intersect : forall A B C A' B' C' G,
A<>B -> B<>C -> A<>C -> G <> A' -> G <> B' -> G <> C' ->
Midpoint A' B C ->
Midpoint B' A C ->
Midpoint C' A B ->
Perp_bisect G A' B C ->
Perp_bisect G B' A C ->
Perp G C' A B.