SOLUTION: An equilateral triangle is inscribed in a circle. If the radius of the circle is 10 cm, calculate the length of a side of the triangle. Answer to nearest whole centimetre.

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Question 924633: An equilateral triangle is inscribed in a circle. If the radius of the circle is 10 cm, calculate the length of a side of the triangle. Answer to nearest whole centimetre.
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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An equilateral triangle is inscribed in a circle.
If the radius of the circle is 10 cm, calculate the length of a side of the triangle. Answer to nearest whole centimetre.
:
After drawing the triangle inside the circle. Draw radii from the center to vertices of the triangle to form 3 equal isosceles triangles which will have angles of 30, 120, 30, the side (s) of the of the triangle is opposite the 120 degree angle.
Use the law of sines to find s
s%2Fsin%28120%29 = 10%2Fsin%2830%29
Cross multiply
.5s = .866 * 10
s = 8.66/.5
s = 17.32 ~ 17 cm