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Mathematics
Mathematics
Problem
In quadrilateral
A
B
C
D
ABCD
A
B
C
D
,
A
B
⊥
B
C
AB \perp BC
A
B
⊥
B
C
and
A
D
⊥
D
C
AD \perp DC
A
D
⊥
D
C
. If
A
B
=
A
D
AB = AD
A
B
=
A
D
, prove that
△
A
B
C
\triangle ABC
△
A
B
C
is congruent to
△
A
D
C
\triangle ADC
△
A
D
C
.
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