The diameter of the circle is given an arbitrary value of 1 ... the interactive determines the length of a side of each triangle, relative to the diameter, based on the angle opposing the side ...

But many people could not tell you what the triangle or circle symbols mean. The white triangle on clothes labels can take four forms: an empty triangle, a triangle with a cross through it ...

Circle, triangle, and square. They’re simple, geometric, and eerily familiar. They look like something pulled straight out of a PlayStation controller or a childhood game of tic-tac-toe.

AO and OC are both radii of the circle. Length AO = Length OC Draw the line OB. It creates two triangles OCB and OAB. These share the length OB.

Image caption, STEP 3: Place the compass at the points where the arcs cross the circle and draw a small ... you now have a regular equilateral triangle.