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Mathematics
Mathematics
Problem
In quadrilateral
A
B
C
D
ABCD
A
B
C
D
, diagonals
A
C
AC
A
C
and
B
D
BD
B
D
intersect at
O
O
O
. It is given that
A
O
=
O
C
AO = OC
A
O
=
O
C
. If
△
A
O
B
≅
△
C
O
D
\triangle AOB \cong \triangle COD
△
A
O
B
≅
△
C
O
D
, prove that
A
B
C
D
ABCD
A
B
C
D
is a parallelogram.
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