The angles in a quadrilateral add up to .

The properties of different kinds of **quadrilaterals** are listed below.

**Square**

a **square** is the only regular quadrilateral

all angles are equal

all sides are of equal length

opposite sides are parallel

the diagonals bisect each other at

the diagonals are equal in length

**Rhombus**

with a **rhombus**, all sides are of equal length

opposite sides are parallel

diagonally opposite angles are equal

the diagonals bisect each other at

**Rectangle**

with a **rectangle**, all angles are equal

opposite sides are of equal length

the diagonals are equal in length

opposite sides are parallel

the diagonals bisect each other

**Parallelogram**

with a **parallelogram**, diagonally opposite angles are equal

opposite sides are of equal length

opposite sides are parallel

the diagonals bisect each other

**Trapezium**

with a **trapezium**, one pair of opposite sides is parallel

**Kite**

with a **kite**, two pairs of sides are of equal length

one pair of diagonally opposite angles is equal

only one diagonal is bisected by the other

the diagonals cross at

Other 2D shapes are considered in the study guide on polygons and circles.