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Angle A is circumscribed about circle O.

What is the measure of angle O?

[picture below]

Angle A is circumscribed about circle O. What is the measure of angle O? [picture-example-1

1 Answer

5 votes

Answer:

134°

Explanation:


In\: \odot O, AB and AC are tangents at points B and C respectively. OB and OC are radii.


\therefore OB\perp AB\: \&\: OC\perp AC

(By tangent radius theorem)


\therefore m\angle ABO =m\angle ACO = 90\degree


m\angle CAB+ m\angle ABO +m\angle ACO+ m\angle BOC = 360\degree


\therefore 46\degree + 90\degree +90\degree+ m\angle BOC = 360\degree


\therefore 226\degree + m\angle BOC = 360\degree


\therefore m\angle BOC = 360\degree-226\degree


\therefore m\angle BOC = 134\degree


\implies m\angle O= 134\degree

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