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Problems
Contests
National and Regional Contests
Romania Contests
Romania Team Selection Test
1991 Romania Team Selection Test
9
9
Part of
1991 Romania Team Selection Test
Problems
(1)
MNPQR , ABCDE similar pentagons, regular?
Source: Romania IMO TST 1991 p9
2/19/2020
The diagonals of a pentagon
A
B
C
D
E
ABCDE
A
BC
D
E
determine another pentagon
M
N
P
Q
R
MNPQR
MNPQR
. If
M
N
P
Q
R
MNPQR
MNPQR
and
A
B
C
D
E
ABCDE
A
BC
D
E
are similar, must
A
B
C
D
E
ABCDE
A
BC
D
E
be regular?
similar
pentagon
geometry
Regular