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Poland - Second Round
1956 Poland - Second Round
2
2
Part of
1956 Poland - Second Round
Problems
(1)
4 equal circumcircles, orthocenter
Source: Polish MO second round 1956 p2
8/29/2024
Prove that if
H
H
H
is the point of intersection of the altitudes of a non-right triangle
A
B
C
ABC
A
BC
, then the circumcircles of the triangles
A
H
B
AHB
A
H
B
,
B
H
C
BHC
B
H
C
,
C
H
A
CHA
C
H
A
and
A
B
C
ABC
A
BC
are equal.
geometry
equal circles
orthocenter