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If O is the centre of the circle, find the value of x in each of the following figures

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#### Solution

In BOC,

OB = OC ...(radii)

So, OCB = OBC = 40°

In BOC,

BOC = 180° - (40° + 40°)

BOC = 180° - 80°

So,

x = `"BOC"/2`

x = `(100°)/2` = 50°.

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