What is a quadrilateral?

A simple closed curve or a polygon formed by four line-segments or sides is called a quadrilateral.

The four line-segments forming a quadrilateral are called its sides.

For example - squares, rectangles, rhombuses, trapeziums and parallelograms are quadrilaterals.

A quadrilateral has four sides and four angles.

The symbol of a quadrilateral is .

Each shape shown below is a quadrilateral.

What is a Quadrilateral?

(i) Shape (d) is a special type of quadrilateral. Its opposite sides are equal. Each angle of it is a right angle. Its name is rectangle.

Shape of a Rectangle

AB = CD, AD = BC and ∠DAB = ∠ABC = ∠BCD = ∠CDA = 90°.

(ii) The quadrilateral (e) is named as square. All the sides of it are of equal measure and each angle is a right angle.

Shape of a Square

In the above figure, AB = BC = CD = DA and ∠ABC = ∠BCD = ∠DAB = ∠CDA = 90°.

(iii) Shape (f) is a quadrilateral having the special name parallelogram and with opposite sides equal and parallel.

It has also its opposite angles equal.

Shape of a Parallelogram

In the above figure, AB and CD are equal and parallel. Similarly, AD and BC are equal and parallel.

∠DAB = ∠DCB and ∠CDA = ∠CBA.

(iv) Shape (g) is the shape of a rhombus whose all sides are equal.

A rhombus is a parallelogram with all its sides equal.

Its two opposite angles are equal and greater than 90°. Its other two opposite angles are equal and less than 90°.

Note: A rhombus cannot have any right angle.

Shape of a Rhombus

In the above figure, AB = BC = CD = DA. AB is parallel to CD and AD is parallel to BC.

∠DAB = ∠DCB and ∠CDA = ∠CBA

No angle is right angle.

(v) The quadrilateral (h) is the shape of a trapezium.

A trapezium is a quadrilateral which has a pair of opposite sides parallel.

Shape of a Trapezium

In the above figure, opposite sides AB and CD are parallel.

A polygon covers a plane space whose area may be calculated. The length of the covering sides is called its perimeter.

Note: The sum of angles of a quadrilateral is always 360°.

Related Concepts on Geometry - Simple Shapes & Circle

Simple Closed Curves


Different Types of Polygons




Circle Math

Line Symmetry

Symmetrical Shapes

4th Grade Math Activities

From Quadrilateral to HOME PAGE

Didn't find what you were looking for? Or want to know more information about Math Only Math. Use this Google Search to find what you need.

New! Comments

Have your say about what you just read! Leave me a comment in the box below. Ask a Question or Answer a Question.

Share this page: What’s this?

Recent Articles

  1. Comparison of Numbers | Compare Numbers Rules | Examples of Comparison

    May 18, 24 02:59 PM

    Rules for Comparison of Numbers
    Rule I: We know that a number with more digits is always greater than the number with less number of digits. Rule II: When the two numbers have the same number of digits, we start comparing the digits…

    Read More

  2. Numbers | Notation | Numeration | Numeral | Estimation | Examples

    May 12, 24 06:28 PM

    Numbers are used for calculating and counting. These counting numbers 1, 2, 3, 4, 5, .......... are called natural numbers. In order to describe the number of elements in a collection with no objects

    Read More

  3. Face Value and Place Value|Difference Between Place Value & Face Value

    May 12, 24 06:23 PM

    Face Value and Place Value
    What is the difference between face value and place value of digits? Before we proceed to face value and place value let us recall the expanded form of a number. The face value of a digit is the digit…

    Read More

  4. Patterns in Numbers | Patterns in Maths |Math Patterns|Series Patterns

    May 12, 24 06:09 PM

    Complete the Series Patterns
    We see so many patterns around us in our daily life. We know that a pattern is an arrangement of objects, colors, or numbers placed in a certain order. Some patterns neither grow nor reduce but only r…

    Read More

  5. Worksheet on Bar Graphs | Bar Graphs or Column Graphs | Graphing Bar

    May 12, 24 04:59 PM

    Bar Graph Worksheet
    In math worksheet on bar graphs students can practice the questions on how to make and read bar graphs or column graphs. Test your knowledge by practicing this graphing worksheet where we will

    Read More