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Question
In the given figure, ABCD is a cyclic quadrilateral. Find the value of x.
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Solution
Here, ABCD is a cyclic quadrilateral; we need to find x.
In a cyclic quadrilateral the sum of opposite angles is equal to 180°.
Therefore,
∠ADC + ∠ABC = 180°
⇒ 180° − 80° + 180° − x = 180°
⇒ x = 100°
Hence, the value of x is 100°.
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