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प्रश्न
ABCD is a cyclic quadrilateral in ∠DBC = 80° and ∠BAC = 40°. Find ∠BCD.
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उत्तर
(ii) It is given that BC || AD ,`angleDBC ` = 80° and `angle BAC` = 40°
We have to find `angleBCD`
`angleBAC = angleBDC `= 40° (Angle in the same segment are equal)
`angleDCB = `180° - (80° + 40° )
= 180° - 120°
= 60°
Hence, `angle BCD ` = 60°
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