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

A quadrilateral is a two-dimensional shape with four straight sides, although the
sides can cross each... ... What are four types of quadrilaterals?

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.mathopenref.com/quadrilateral.html

Quadrilateral definition and properties. ... Quadrangle ("four angles") is another
name for a quadrilateral. However, it is a word often ... Types of quadrilateral ...

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 ...

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.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
).

www.dkfindout.com/us/math/geometry/types-quadrilateral/

Quadrilaterals are shapes with four sides. There are different names for the types
of quadrilateral. A quadrilateral's name depends on the length of the sides, the ...

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
...