Tessellation by Rotation

This tessellation was created by starting with an equilateral triangle, which you can see by pressing Show Equilateral Triangle. Jagged edges were created along each side of the triangle and a polygon was constructed between the vertices of these jagged edges. Press Show Original Polygon and drag the points to change the tessellation.

After generating some interesting visual effects, see if you can figure out how the tessellation was created. Here are a few hints. Press Hide Completed Tessellation to see an earlier stage of its development. One of the jagged sides of the original polygons is a rotation of another jagged edge. The third jagged edge is based upon a 180-degree rotation around the midpoint of one side of the equilateral triangle.

After the original polygon was created, it was rotated five times around the same point to create half of the earlier stage. By how much was it rotated? How was the second half of the earlier stage created?

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