#### Question

In the following figures, O is the centre of the circle. Find the values of a, b, c and d

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#### Solution

∠AOB = 2 ∠AOB = 2×50°= 100°

(Angle at the centre is double the angle at the circumference subtended by the same chord)

Also, OA = OB

⇒ ∠OBA = ∠OAB = C∴ `c = (180° - 100°)/2 = 40°`

Is there an error in this question or solution?

Solution In the Following Figures, O is the Centre of the Circle. Find the Values of A, B, C and D. Concept: Chord Properties - Chords Equidistant from the Center Are Equal (Without Proof).