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Find the value of b.

Find the value of b.-example-1
User Psychotechnopath
by
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1 Answer

25 votes
25 votes

Answer:
230^{\circ

Explanation:

For convenience, I labeled some points as shown in the attached picture.

Also, I assume
\overline{AB} and
\overline{BC} are tangents to the circle.


  1. \overline{BO} \cong \overline{BO} (reflexive property)

  2. \overline{AB} \cong \overline{BC} (tangents drawn from a common external point are congruent)

  3. \angle BAO \cong \angle BCO (right angles are congruent)

Therefore, we know
\triangle ABO \cong \triangle CBO by HL.

Thus, by CPCTC,


\angle AOB \cong \angle BOC \implies m\angle BOC=65^(\circ)\\\\\implies m\angle AOC=130^(\circ)

This means the measure of minor arc AC is
130^(\circ), and thus
b=360^(\circ)-130^(\circ)=\boxed{230^(\circ)}

Find the value of b.-example-1
User Macandyp
by
2.9k points