Question

BCDE is a cyclic quadrilateral​

Answer 1

Answer:35^0

Step-by-step explanation:In given figure ABCD is a cyclic quadrilateral.

We know that, sum of the opposite angles in a cyclic quadrilateral is 180  

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So, ∠BCD + ∠BAD = 180  

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⇒  125  

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 + ∠BAD = 180  

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⇒  ∠BAD = 180  

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 - 125  

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∴  ∠BAD = 55  

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   ----   (1)

Since, ∠ABD is an angle in semi-circle.

∴ ∠ABD = 90  

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      --- (2)

In △ABD,

∠ADB + ∠ABD + ∠BAD = 180  

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∠ADB + 90  

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 + 55  

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 = 180  

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    (From 1 and 2)

∴  ∠ADB = 35  

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