Why is a rhombus not necessarily a regular polygon?

Question

Eva Adamson · Accepted Answer

A rhombus does not have to be equiangular.

A regular polygon must be equilateral (all sides the same length) and equiangular (all internal angle sof the same size). A rhombus has 4 sides of equal length and opposite angles are equal but not all angles are equal. A rhombus may be shaped like a diamond. A rhombus that is equiangular is called a square.

Eva Abramson · Answer

A regular polygon needs all sides and all angles to be equal, whereas a rhombus only needs all sides to be equal.

A rhombus is a 4-sided polygon in which all sides are of equal length. While this fulfills one of the requirements of being a regular polygon, it need not have all of is angles be equal as well.

For example, this is a rhombus which is not a regular polygon:

Its sides are of equal length, but it clearly has different angles.

Avery Alexander · Answer

undefined A rhombus is not necessarily a regular polygon because, while all its sides are of equal length (a requirement for regular polygons), the angles between the sides of a rhombus are not necessarily equal. A regular polygon must have all sides and all angles equal. In a rhombus, the opposite angles are equal to each other but not necessarily to 90 degrees, which means the angles can differ, preventing it from being a regular polygon unless it becomes a square (where all sides and angles are equal).