A Quadrilateral has four-sides, it is 2-dimensional (a flat shape), closed (the lines join up), and has straight sides.

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Try it Yourself

(Also check out this on Interactive Quadrilaterals)


A quadrilateral has:

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


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

Types of Quadrilaterals

Tright here are special kinds of quadrilateral:


Some types are also contained in the interpretation of various other types! For example a square, rhombus and also rectangle are likewise parallelograms. See below for more details.

Let us look at each type in turn:

The Rectangle

the bit squares in each corner intend "appropriate angle"

A rectangle is a four-sided shape wright here eexceptionally angle is a ideal angle (90°).

Also opposite sides are parallel and of equal size.

The Square

the little squares in each edge intend "appropriate angle"

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

Also opposite sides are parallel.

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

The Rhombus


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

Also opposite sides are parallel and also oppowebsite angles are equal.


Another amazing thing is that the diagonals (daburned lines) satisfy in the middle at a right angle. In various other words they "bisect" (cut in half) each other at best angles.

A rhombus is occasionally dubbed a rhomb or a diamond.

The Parallelogram


A parallelogram has actually opposite sides parallel and equal in length. Also opposite angles are equal (angles "A" are the same, and angles "B" are the same).

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


A parallelogram with:

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

is a square!

The Trapezoid (UK: Trapezium)


Isosceles Trapezoid

A trapezoid (referred to as a trapezium in the UK) has a pair of oppowebsite sides parallel.

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

In the US:a pair of parallel sidesNO parallel sides
In the UK:NO parallel sidesa pair of parallel sides
(the US and also UK meanings are swapped over!)

An Isosceles trapezoid, as displayed above, has left and appropriate sides of equal size that sign up with to the base at equal angles.

The Kite


Hey, it looks favor a kite (usually).

It has actually 2 pairs of sides:

Each pairis made of 2 equal-length sides that join up.


the angles where the two pairs fulfill are equal.the diagonals, shown as dashed lines above, meet at a appropriate angle.one of the diagonals bisects (cuts equally in half) the various other.

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

Ircontinual Quadrilaterals

The only consistent (all sides equal and all angles equal) quadrilateral is a square. So all other quadrilaterals are irregular.

The "Family Tree" Chart

Quadrilateral definitions are inclusive.

Example: a square is also a rectangle.

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

(We don"t say "Having all 90° angles provides it a rectangle other than when all sides are equal then it is a square.")

This might seem odd, as in day-to-day life we think of a square as not being a rectangle ... but in math it is.

Using the chart listed below we can answer such concerns as:

Is a Square a type of Rectangle? (Yes) Is a Rectangle a type of Kite? (No)


Complex Quadrilaterals

Oh Yes! when 2 sides cross over, we contact it a "Complex" or "Self-Intersecting" quadrilateral, favor these:


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


A quadrilateral is a polygon. In truth it is a 4-sided polygon, simply choose a triangle is a 3-sided polygon, a pentagon is a 5-sided polygon, and so on.

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Play through Them

Now that you understand the different kinds, you deserve to play through the Interenergetic Quadrilaterals.

Other Names

A quadrilateral have the right to occasionally be called:

a Quadrangle ("4 angles"), so it sounds like "triangle" a Tetragon ("four polygon"), so it sounds choose "pentagon", "hexagon", and so on
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Polygons Interactive Quadrilaterals Right Angle Parallel Parallelogram In Any Quadrilateral Geomeattempt Index