SOLUTION: A chord of a circle is 18cm long and subtends an angle of 110° at the centre. Find the radius of the circle.

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Question 1191157: A chord of a circle is 18cm long and subtends an angle of 110° at the centre. Find the radius of the circle.
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!


Split the triangle into two congruent right triangles:



sin%2855%5Eo%29=opposite%2Fhypotenuse=9%2Fr

You finish by solving that for r.

Edwin