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Mathematics
Mathematics
Problem
Prove that the lengths of the tangents drawn from an external point to a circle are equal. Using the above theorem, prove that
A
B
+
C
D
=
A
D
+
B
C
AB + CD = AD + BC
A
B
+
C
D
=
A
D
+
B
C
, if a quadrilateral ABCD is drawn to circumscribe a circle.
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