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1989 IMO Shortlist
32
32
Part of
1989 IMO Shortlist
Problems
(1)
ABC is equidistant from the circumcenter O
Source: IMO Shortlist 1989, Problem 32, ILL 103
9/18/2008
The vertex
A
A
A
of the acute triangle
A
B
C
ABC
A
BC
is equidistant from the circumcenter
O
O
O
and the orthocenter
H
.
H.
H
.
Determine all possible values for the measure of angle
A
.
A.
A
.
geometry
circumcircle
trigonometry
parallelogram
rhombus
angle
IMO Shortlist