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The Equilateral Triangle

An equilateral triangle is a three sided polygon, basically! It's construction is very simple. There are two ways you can construct it: 1. Inscribing it in a circle. 2. Constructing it knowing only one side. Both types will be covered.

This first method is inscribing. Given circle O:
  1. Select any point on the circle. Call it A.
  2. Draw a circle at point A with radius OA. Where it intersects the original circle, call it B.
  3. Draw a circle at B with radius OB. Call the point it intersects the original circle, C.
  4. Draw a circle at C with radius CA. Where it intersects the original circle, call it D.
  5. ACD is an equilateral triangle.
This is the method of constructing a triangle knowing only one side of it. Given side AB:
  1. Draw two circles, one at A and one at B. Both should have a radius of AB.
  2. Circles A and B intersect at point C. ABC is an equilateral triangle.

        © 2003 Robin Hu