Final Cover - For Printing

Module 72 : Quadrilaterals

QUADRILATERALS

1. Polygon
   A polygon is a plane figure formed by many line segments. The word ‘poly’ means
   many.

Square, rectangle, rhombus, pentagon, hexagon, etc., are all polygons. Provision of

concrete polygons made out of thick boards and exploration may enable the child to

understand the idea of polygons.

2. Regular polygon
   If the sides and angles of a polygon are equal, then it is known as regular polygon.
   A polygon of five sides is called as a pentagon, a polygon of six sides is a hexagon and
   a polygon of eight sides is an octagon.

The child may be provided with a square and after exploration of its sides, the child

may be able to understand that all four sides of the square are equal. Once the child

is able to realize that the sides are equal, the idea that if all sides are equal then the

geometrical figure may be termed as regular polygon is to be explained.

3. Quadrilateral
   A quadrilateral is a closed geometrical figure on a plane formed by four line segments.
   In other words, any geometrical figure having four straight sides is called a