MHB Finding distance between two adjacent objects

[chr1is]

I have a question:

Holes are to be drilled in a metal plate at 12 equally spaced locations around a circle with a radius of 16.40 cm. Find the distance between two adjacent holes.

How do I draw the figure? And would I have to multiply 16.40 by 2 to get the distance?

 

[MarkFL]

One way would be to use the Law of Cosines...form an isosceles triangle using the center of the circle and two adjacent holes...you know the two equal sides of the triangle are the radius of the circle, and you know the angle subtending these sides, so you can find the third side using the Law of Cosines. You could also use the Law of Sines here as well, which would likely be computationally simpler.