SOLUTION: A 72-degree arc AB is drawn in a circle of radius 8 cm. How long is chord AB?

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Question 1158194: A 72-degree arc AB is drawn in a circle of radius 8 cm. How long is chord AB?
Answer by greenestamps(13200) About Me  (Show Source):
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The arc is 72 degrees, so the central angle is 72 degrees.

Draw the segment from the center of the circle perpendicular to chord AB. That segment bisects the 72 degree central angle; it also bisects chord AB.

Then in either of the two right triangles we have

sin%2836%29+=+%28AB%2F2%29%2F8

Use a calculator (or the value of sin(36), if you know it) to solve for the length AB.