A quadrilateral has four-sides, that is 2-dimensional (a level shape), closed (the lines sign up with up), and has straight sides.

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A square has:

4 sides (edges) 4 vertices (corners) inner angles that add to 360 degrees:


Try drawing a quadrilateral, and measure the angles. They should add to 360°

Types that Quadrilaterals

There are special species of quadrilateral:


Some species are likewise included in the an interpretation of other types! For instance a square, rhombus and rectangle are also parallelograms. See below for much more details.

Let us look at each type in turn:

The Rectangle

the tiny squares in each edge mean "right angle"

A rectangle is a four-sided form where every edge is a ideal angle (90°).

Also the contrary sides room parallel and also of same length.

The Square

the little squares in each edge mean "right angle"

A square has equal sides (marked "s") and also every angle is a ideal angle (90°)

Also the contrary sides are parallel.

A square likewise fits the meaning of a rectangle (all angles space 90°), and also a rhombus (all sides are equal length).

The Rhombus


A rhombus is a four-sided shape where all sides have equal size (marked "s").

Also opposite sides room parallel and opposite angles room equal.


Another amazing thing is the the diagonals (dashed lines) fulfill in the center at a best angle. In other words they "bisect" (cut in half) each various other at ideal angles.

A rhombus is sometimes referred to as a rhomb or a diamond.

The Parallelogram


A parallelogram has actually opposite political parties parallel and equal in length. Likewise opposite angles space equal (angles "A" room the same, and also angles "B" space the same).

NOTE: Squares, Rectangles and also Rhombuses are all Parallelograms!


A parallelogram with:

all sides equal andangles "A" and also "B" as appropriate angles

is a square!

The Trapezoid (UK: Trapezium)


Isosceles Trapezoid

A trapezoid (called a trapezium in the UK) has actually a pair of opposite political parties parallel.

And a trapezium (called a trapezoid in the UK) is a quadrilateral with NO parallel sides:

In the US:a pair that parallel sidesNO parallel sides
In the UK:NO parallel sidesa pair the parallel sides
(the US and UK interpretations are swapped over!)

An Isosceles trapezoid, as shown above, has left and also right sides of equal size that join to the basic at same angles.

The Kite


Hey, it looks prefer a kite (usually).

It has actually two pairs of sides:

Each pairis do of two equal-length sides that join up.


the angles wherein the 2 pairs accomplish are equal.the diagonals, displayed as dashed lines above, satisfy at a appropriate angle.one of the diagonals bisects (cuts same in half) the other.

... And also that"s it for the one-of-a-kind quadrilaterals.

Irregular Quadrilaterals

The only continuous (all sides equal and also all angles equal) quadrilateral is a square. For this reason all various other quadrilaterals are irregular.

The "Family Tree" Chart

Quadrilateral definitions are inclusive.

Example: a square is likewise a rectangle.

So we include a square in the definition of a rectangle.

(We don"t say "Having every 90° angles renders it a rectangle other than when all sides room equal climate it is a square.")

This may seem odd, as in day-to-day life we think of a square together not gift a rectangle ... Yet in mathematics it is.

Using the chart below we have the right to answer such questions as:

Is a Square a kind of Rectangle? (Yes) Is a Rectangle a form of Kite? (No)


Complex Quadrilaterals

Oh Yes! as soon as two sides cross over, we speak to it a "Complex" or "Self-Intersecting" quadrilateral, like these:


They still have actually 4 sides, yet two political parties cross over.


A quadrilateral is a polygon. In reality it is a 4-sided polygon, just like a triangle is a 3-sided polygon, a pentagon is a 5-sided polygon, and so on.

See more: Is It Is Permissible To Eat While Preparing Food In The Kitchen

Play v Them

Now the you know the different types, you can play v the interactive Quadrilaterals.

Other Names

A quadrilateral deserve to sometimes it is in called:

a Quadrangle ("four angles"), so the sounds favor "triangle" a Tetragon ("four polygon"), so it sounds choose "pentagon", "hexagon", etc.
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polygons Interactive Quadrilaterals appropriate Angle Parallel parallel In any kind of Quadrilateral Geometry Index