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Mathematics
Mathematics
Problem
Diagonals
A
C
AC
A
C
and
B
D
BD
B
D
of quadrilateral
A
B
C
D
ABCD
A
B
C
D
intersect at
O
O
O
. If
O
A
=
O
C
OA = OC
O
A
=
O
C
and
O
B
=
O
D
OB = OD
O
B
=
O
D
, prove that
A
B
C
D
ABCD
A
B
C
D
is a parallelogram.
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