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2011 JHMT
7
7
Part of
2011 JHMT
Problems
(1)
2011 JHMT Geometry #7
Source:
9/5/2023
Let
A
B
C
D
ABCD
A
BC
D
be a cyclic quadrilateral with
A
B
=
6
AB = 6
A
B
=
6
,
B
C
=
12
BC = 12
BC
=
12
,
C
D
=
3
CD = 3
C
D
=
3
, and
D
A
=
6
DA = 6
D
A
=
6
. Let
E
,
F
E, F
E
,
F
be the intersection of lines
A
B
AB
A
B
and
C
D
CD
C
D
, lines
A
D
AD
A
D
and
B
C
BC
BC
, respectively. Find
E
F
EF
EF
.
geometry