I'm writing a homework for my middle school students, who are helping Inspector Heptagon of Flatland Yard narrow his list of 2D suspects based solely on eye-witness descriptions.
Given the description "Plane looking fellow, six equal sides, not sure what his angle was" the obvious conclusion is a regular hexagon, so I drew an equilateral hexagonal lightning bolt to deconstruct their geometric stereotyping:
https://www.geogebra.org/geometry/eR2Gje5t
I'm looking for the correct word to end my description of the Geogebra construction, to say that moving its vertices won't change the lengths of its sides: "... equilateral hexagonal lightning bolt - you can drag the points to change its shape, but not its equilateralness"