QUADRILATERALS

Curve: A figure formed on a plane surface by joining a number of points without lifting a pencil is called a curve.

Open Curve: A curve which does not end at the same starting point or which does not cut itself is called an open curve.

Closed Curve: A curve which cut itself or which starts and ends at the same point is called a closed curve.

Simple Closed Curve: A closed curve called a simple closed curve which does not intersect itself.

 A polygon is a closed figure bounded by three or more line segments such that each line segment intersects exactly two other points (vertices)

A simple closed figure bounded by four line segments is called a quadrilateral, it has four sides i.e., AB, BC, CD and AD and four vertices as A, B, C and D and the sum of all angles of a quadrilateral is 360°

TRIANGLE

QUADRILATERAL

PENTAGON

HEXAGON

SEPTAGON

OCTAGON

NONAGON

DECAGON