A quadrilateral is plane figure bounded by four straight lines. The straight line joining the opposite corners is called its diagonal. The diagonal of a quadrilateral divides it into two triangles. The perpendiculars on a diagonal from two opposite corners are known as its offsets. It should be remembered that the sum of all the interior angles of a quadrilateral is equal to four fight angles.
Types of Quadrilaterals
There are different types of quadrilaterals: