What is the formula for approximating the Segment Edge Length?

What is the formula for approximating the Segment Edge Length?

SEL = Circumference divided by number of segments = (Pi * Diameter) ÷ number of segments. Example SEL of 8″ diameter 12-segment ring: SEL = (3.1416 * 8) ÷ 12 = 25.1328 ÷ 12 = 2.09″.

Cutting Angle = (360 ÷ 12) ÷ 2) = 15°