Maths Chapter 03: Understanding Quadrilaterals

Class 08 Maths NCERT

You know that the paper is a model for a plane surface. When you join a number of points without lifting a pencil from the paper (and without retracing any portion of the drawing other than single points), you get a plane curve.

A simple closed curve made up of only line segments is called a polygon.

Parallelogram: A quadrilateral with each pair of opposite sides parallel.

1. Opposite sides are equal.
2. Opposite angles are equal.
3. Diagonals bisect one another.

Rhombus: A parallelogram with sides of equal length.

1. All the properties of a parallelogram.
2. Diagonals are perpendicular to each other.

Rectangle: A parallelogram with a right angle.

1. All the properties of a parallelogram.
2. Each of the angles is a right angle.
3. Diagonals are equal.

Square: A rectangle with sides of equal length.

1. All the properties of a parallelogram, rhombus and a rectangle.

Kite: A quadrilateral with exactly two pairs of equal consecutive sides.

1. The diagonals are perpendicular to one another
2. One of the diagonals bisects the other.