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Poland Contests
Poland - Second Round
1964 Poland - Second Round
2
2
Part of
1964 Poland - Second Round
Problems
(1)
perpenidicularity, joining arc midpoints
Source: Polish MO Second Round 1964 p2
8/31/2024
The circle is divided into four non-overlapping gaps
A
B
AB
A
B
,
B
C
BC
BC
,
C
D
CD
C
D
and
D
A
DA
D
A
. Prove that the segment joining the midpoints of the arcs
A
B
AB
A
B
and
C
D
CD
C
D
is perpendicular to the segment joining the midpoints of the arcs
B
C
BC
BC
and
D
A
DA
D
A
.
geometry
perpendicular
arc midpoint