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Mathematics
Mathematics
Problem
In parallelogram
A
B
C
D
ABCD
A
B
C
D
, diagonal
A
C
AC
A
C
is drawn. If
∠
A
B
C
=
72
∘
\angle ABC = 72^{\circ}
∠
A
B
C
=
7
2
∘
, find
∠
C
D
A
\angle CDA
∠
C
D
A
.
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