Quadrilateral

A quadrilateral is a four-sided polygon. The interior angles of any quadrilateral add up to 360º. The quadrilaterals you should know are:

  • Square – this has four sides of equal length and four equal (90º) angles. This means that it has two pairs of parallel sides.
  • Rectangle – this has four equal (90º) angles and opposite sides of equal length. This has two pairs of parallel sides.
  • Parallelogram – this has opposite sides of equal length. This has two pairs of parallel sides. This has two pairs of equal angles at opposite corners or vertices.
  • Rhombus – this has four sides of equal length. This means that it has two pairs of parallel sides – so a rhombus is a special parallelogram; one with four equal sides.
  • Trapezium – this has four sides, exactly two of which are parallel.
  • Kite – this has two pairs of adjacent equal sides. This has one pair of equal angles at opposite vertices.

Relevant lessons: