Trapezium

A trapezoid is a transparent geometric figure with four equal sides and rounded corners, which has no height and whose base is a rectangle. The alternative name and other forms of trapezoid (terms also used for it: emphase, parallelogram, rhombohydra) are associated with its profile: thus, asymmetrical trapezoidal and trapezoidal theoretical figures belong to other varieties of the general trapezoid.

The article that interests us deals with the first of the listed options. It also has one interesting property: it is the most symmetrical when compared with other types of trapezoid. So