Mathematics
O is the center of the circle, OB = BC and ∠BOC = 20°.

Statement (1) : x = 2 x 20° = 40°
Statement (2) : ∠BOC = 20°.
x = ∠OAB + 20° = ∠OBA + 20° = 40° + 20° = 60°
Both statements are true.
Both statements are false.
Statement 1 is true, and statement 2 is false.
Statement 1 is false, and statement 2 is true.
Circles
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Answer
Given,
⇒ OB = OC
⇒ ∠BOC = ∠BCO = 20° (Angles opposite to equal sides of a triangle are always equal)
In △ OBC, using angle sum property,
⇒ ∠OBC + ∠BCO + ∠BOC = 180°
⇒ ∠OBC + 20° + 20° = 180°
⇒ ∠OBC + 40° = 180°
⇒ ∠OBC = 180° - 40°
⇒ ∠OBC = 140°
∠OBC and ∠OBA forms linear pairs of angle.
⇒ ∠OBC + ∠OBA = 180°
⇒ 140° + ∠OBA = 180°
⇒ ∠OBA = 180° - 140°
⇒ ∠OBA = 40°
Since OB = OA (Radii of same circle)
⇒ ∠OBA = ∠OAB = 40° (Angles opposite to equal sides of a triangle are always equal)
Using exterior angle property, the exterior angle of a triangle is equal to the sum of the two opposite interior angles.
In triangle OAC,
⇒ ∠EOA = ∠OAC + ∠OCA
⇒ x = ∠OAB + 20°
⇒ x = ∠OBA + 20° = 40° + 20° = 60°
So, statement 1 is false and statement 2 is true.
Hence, option 4 is the correct option.
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