A parallelogram with all sides congruent is called a rhombus. All the sides of a rhombus are equal in length, which is why it is also called an equilateral quadrilateral. Other names commonly used to refer to a rhombus are "lozenge" and "diamond."
Continue ReadingA rhombus has equal opposite angles; two of its diagonals are perpendicular, and its diagonals bisect opposite angles. A quadrilateral is a rhombus only if all sides of the quadrilateral are of equal length or if each diagonal bisects two opposite interior angles. A rhombus is a parallelogram in which the diagonals are perpendicular or at least two consecutive sides are equal in length.
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