Different forms of forms differ from each other in terms of sides or angles. Many shapes have 4 sides, however the distinction in angles on their sides makes them unique. We speak to these 4-sided forms the quadrilaterals.

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In this write-up, you will learn:

What a quadrilateral is.How the different types of quadrilaterals look like.The properties of quadrilaterals.


What is a Quadrilateral?

As the word argues, ‘Quad’ suggests four and ‘lateral’ means side. Because of this a quadrilateral is a closed two-dimensional polygon made up of 4-line segments. In basic words, a quadrilateral is a shape via four sides.

Quadrilaterals are everywhere! From the books, chart records, computer system keys, tv, and mobile screens. The list of real-human being examples of quadrilaterals is endmuch less.

Types of Quadrilaterals

There are 6 quadrilaterals in geometry. Some of the quadrilaterals are sucount familiar to you, while others might not be so familiar.

Let’s take a look.


 A rectangle

A rectangle is a quadrilateral through 4 appropriate angles (90°). In a rectangle, both the pairs of oppowebsite sides are parallel and equal in length.


Properties of a rhombus

All sides are congruent by interpretation.The diagonals bisect the angles.The diagonals in a kite bisect each various other at appropriate angles.


Properties of Quadrilaterals

The properties of quadrilaterals include:

Eincredibly quadrilateral has actually 4 sides, 4 vertices, and also 4 angles.4The complete measure of all the 4 inner angles of a quadrilateral is always equal to 360 degrees.The amount of interior angles of a quadrilateral fits the formula of polygon i.e.

Sum of inner angles = 180 ° * (n – 2), wbelow n is equal to the variety of sides of the polygon

Rectangles, rhombus, and also squares are all types of parallelograms.A square is both a rhombus and also a rectangle.The rectangle and rhombus are not square.A parallelogram is a trapezium.A trapezium is not a parallelogram.Kite is not a parallelogram.

Classification of quadrilaterals

The quadrilaterals are classified into two basic types:

Convex quadrilaterals: These are the quadrilaterals with internal angles less than 180 levels, and also the two diagonals are inside the quadrilaterals. They include trapezium, parallelogram, rhombus, rectangle, square, kite, and so on.Concave quadrilaterals: These are the quadrilaterals with at leastern one internal angle greater than 180 levels, and at leastern one of the two diagonals is outside the quadrilaterals. A dart is a concave quadrilateral.

Tbelow is one more less widespread form of quadrilaterals, referred to as complicated quadrilaterals. These are crossed figures. For example, crossed trapezoid, crossed rectangle, crossed square, etc.

Let’s job-related on a few example problems about quadrilaterals.

Example 1

The inner angles of an ircontinual quadrilateral are; x°, 80°, 2x°, and 70°. Calculate the worth of x.


By a residential or commercial property of quadrilaterals (Sum of internal angles = 360°), we have actually,

⇒ x° + 80° + 2x° + 70° =360°


⇒ 3x + 150° = 360°

Subtract 150° on both sides.

⇒ 3x + 150° – 150° = 360° – 150°

⇒ 3x = 210°

Divide both sides by 3 to get;

⇒ x = 70°

Thus, the worth of x is 70°

And the angles of the quadrilaterals are; 70°, 80°, 140°, and 70°.

Example 2

The internal angles of a quadrilateral are; 82°, (25x – 2) °, (20x – 1) ° and (25x + 1) °. Find the angles of the quadrilateral.


The total amount of inner angles of in a quadrilateral = 360°

⇒ 82° + (25x – 2) ° + (20x – 1) ° + (25x + 1) ° = 360°

⇒ 82 + 25x – 2 + 20x – 1 + 25x + 1 = 360


⇒ 70x + 80 = 360

Subtract both sides by 80 to get;

⇒ 70x = 280

Divide both sides by 70.

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⇒ x = 4

By substitution,

⇒ (25x – 2) = 98°

⇒ (20x – 1) = 79°

⇒ (25x + 1) = 101°

Therefore, the angles of the quadrilateral are; 82°, 98°, 79°, and also 101°.

Practice Questions

Consider a parallelogram PQRS, whereFind the 4 interior angles of the rhombus whose sides and one of the diagonals are of equal size.