These are the equilateral triangle, the square and the regular hexagon.
Are you aware, Mr Gascoigne, of the properties of an equilateral triangle?
These are the equilateral triangle, the square, and the regular hexagon.
Form of the outer shell not a sphere, but a regular octahedron, with eight congruent, equilateral triangular even faces.
Cortical shell hexangular, equilateral, ...