A quadrilateral is a topic in Euclidean geometry, which deals with polygons that contain four vertices and four sides. Quadrilaterals are of 2-dimensional structures. They can be classified into five major types. Trapezium The trapezium is a 2-dimensional shape that has a pair of parallel sides. NCERT Class 9 Maths Chapter 8 Quadrilaterals deals with the Angle Sum Property of a Quadrilateral, Types of Quadrilaterals such as Trapezium, Parallelograms, Rectangle, Rhombus, Square, and Kite. It further elucidates the Properties of a Parallelogram and Conditions for a Quadrilateral to be a Parallelogram.For example, in an isosceles trapezium, the angles on the opposite sides parallel to each other are equal. These angles are commonly known as the base angles.
Features of Trapezium
A figure that has opposite sides parallel to each other is known as a parallelogram. Apart from that, the sides opposite to each other are equal.
Features of Parallelogram
Figure of a Parallelogram
The given below are some of the fundamental formulae related to a parallelogram
Perimeter of parallelogram = 2 (L + B)
Area of Parallelogram = L * H
A rhombus has all its four sides equal in terms of length. Therefore, diagonals present in a rhombus are perpendicular bisectors to one another.
Features of Rhombus
If m and n are the diagonals of a rhombus, then,
Perimeter of Rhombus = 4 L
Area of Rhombus = (a * b) / 2
A rectangle is another type of parallelogram that has all the angles equal to right angles. In a rectangle, opposite sides have the same length.
Properties of Rectangle
Following are the formulae related to rectangle,
Perimeter of Rectangle = 2 (L + B)
Area of Rectangle = L * B
A square is one of the most basic shapes in a quadrilateral that contains four equal sides in terms of length. All the four angles present in a square are also equal. Therefore, they are all right angles.
Properties of Square
Formulae related to the square are mentioned below,
Perimeter of Square = 4 L
Are of Square = L2