en.wikipedia.org/wiki/Quadrilateral

Some types of quadrilaterals. Edges and vertices, 4. Schläfli symbol, {4} (for
square). Area, various methods; see below. Internal angle (degrees), 90° (for
square and rectangle). In Eucli...

www.mathsisfun.com/quadrilaterals.html

A Quadrilateral has four-sides, it is 2-dimensional (a flat shape), closed (the lines
... Some types are also included in the definition of other types! ... Other Names.

www.dummies.com/how-to/content/identifying-the-seven-quadrilaterals.html

Rhombus: A quadrilateral with four congruent sides; a rhombus is both a kite and
a ... Rectangle: A quadrilateral with four right angles; a rectangle is a type of ...

www.math-only-math.com/different-types-of-quadrilaterals.html

Different types of quadrilaterals are explained with their definition and properties
along with the diagram. Parallelogram A quadrilateral is called a parallelogram.

www.reference.com/math/quadrilateral-parallelogram-5f25e29d0bf71259

A quadrilateral is a two-dimensional shape with four straight sides, although the
sides can ... What are four types of quadrilaterals? ... specific names; for instance,
a shape that has four unequal sides is a quadrilateral but not a parallelogram.

thinkmath.edc.org/resource/shape-quadrilateral

A quadrilateral is a polygon that has exactly four sides. ... Just as triangles and
quadrilaterals are special types of polygons, there are many subclasses of ... The
square is also the name of the regular quadrilateral -- one in which all sides are ...

www.ask-math.com/types-of-quadrilateral.html

This page is about types of quadrilateral. ... In this section we will discuss different
types of quadrilateral. Quadrilateral : It is a closed figure formed by 4 line ...

www.cut-the-knot.org/Curriculum/Geometry/Quadrilaterals.shtml

Quadrilateral is a geometric shape that consists of four points (vertices)
sequentially ... summarize the relationship between various kinds of
quadrilaterals: ... Here is a list of all the properties of quadrilaterals that we have
mentioned along with ...

study.com/academy/lesson/what-is-a-quadrilateral-definition-properties-types-example.html

We name each vertex with a capital letter. Let's name our quadrilateral with the
four vertices: P, N, C, and L. It also has four sides: the segments PN, NC, CL, and
...

www.math.com/school/subject3/lessons/S3U2L3DP.html

There are many different kinds of quadrilaterals, but all have several things in
common: all of them have four sides, are coplanar, have ... A rectangle has two
pairs of opposite sides parallel, and four right angles. ... (British name: Trapezium
).