SOLUTION: How do I find the Measure of arc BC? <a href="http://s155.photobucket.com/albums/s291/jesseatle/?action=view&current=geom7.jpg" target="_blank"><img src="http://i155.photobucket

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Question 139573: How do I find the Measure of arc BC?
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Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
How do I find the Measure of arc BC?

Arc BC is is subtended by the inscribed angle BAC.

Theorem to use:
The measure of an arc subtended by an inscribed angle is twice
the measure of the inscribed angle. 

Since the sum of the measures of the angles of triangle ABC is
180°, 

m(angle A) + m(angle B) + m(angle C) = 180°

              m(angle A) + 68° + 62° = 180°

                   m(angle A) + 130° = 180°
                               -130°  -130°
                 ---------------------------
                          m(angle A) =  50°

So by the theorem, the measure of arc BC is twice 50° or 100°.

Edwin