# Rhombus

## Rhombus

A quadrilateral with four congruent sides and congruent opposite angles.

### Properties

• Rhombuses belong to the class of parallelograms; they are parallelograms with four congruent sides.
• The two diagonals of a rhombus are perpendicular.
• The opposite sides of a rhombus are parallel.
• A rhombus has two axes of symmetry.

Based on its properties, a rhombus belongs to the family of convex quadrilaterals, trapezoids and parallelograms.

### Formulas

The perimeter P of a rhombus with side length c is given by : $$P=4c$$.

The area A of a rhombus with a short diagonal $$d$$ and a long diagonal $$D$$ is given by : $$A=frac{Dtimes d}{2}$$