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Baltic Way
2015 Baltic Way
11
11
Part of
2015 Baltic Way
Problems
(1)
Geometry
Source: Baltic Way 2015
11/8/2015
The diagonals of parallelogram
A
B
C
D
ABCD
A
BC
D
intersect at
E
E
E
. The bisectors of
∠
D
A
E
\angle DAE
∠
D
A
E
and
∠
E
B
C
\angle EBC
∠
EBC
intersect at
F
F
F
. Assume
E
C
F
D
ECFD
ECF
D
is a parellelogram . Determine the ratio
A
B
:
A
D
AB:AD
A
B
:
A
D
.
geometry
parallelogram
ratio