415
edits
Changes
Jump to navigation
Jump to search
mLine 1:
Line 1: − + − +
no edit summary
A quadrilateral is a [[polygon]] with four sides.
A quadrilateral is a [[polygon]] with four sides.
As a consequence of the definition, the sum of the angles in a quadrilateral equal 360<sup>0</sup>, and all quadrilaterals are capable of [[tessellation|tessellating]] an [[infinite]] plane.
As a consequence of the definition, the sum of the angles in a quadrilateral equals 360<sup>0</sup>, and all quadrilaterals are capable of [[tessellation|tessellating]] an [[infinite]] plane.
===Classification of Quadrilaterals===
===Classification of Quadrilaterals===
The [[classification]] of quadrilaterals is complex, as there are several intersecting sub-categories:
The [[classification]] of quadrilaterals is complex, as there are several intersecting sub-categories:
* A (British) [[trapezium]] or (American) [[trapezoid]] has one pair of opposite sides parallel. A version of this called the [[isoceles trapezium]] also has one pair of opposite sides equal
* A (British) [[trapezium]] or (American) [[trapezoid]] has one pair of opposite sides parallel. A version of this called the [[isosceles trapezium]] has the other pair of opposite sides equal
* A [[parallelogram]] has two pairs of opposite sides parallel (and equal)
* A [[parallelogram]] has two pairs of opposite sides parallel (and equal)
* A [[rectangle]] has four right angles
* A [[rectangle]] has four right angles