Quadrilaterals
Quadrilaterals ° What is quadrilateral? A plane, closed figure bounded by four line segments is called quadrilateral. There are different types of quadrilaterals, they are trapezium, parallelogram, rhombus, rectangle, square. • What is the sum of all the interior angles of a quadrilateral? The sum of all the interior angles of a quadrilateral is 360 degree. Important Formulae Special quadrilaterals Parallelogram - A parallelogram is a quadrilateral with both pairs of opposite sides parallel. Important points - Opposite sides of a parallelogram are equal Opposite angles of a parallelogram are equal The diagonals of a parallelogram bisect one another. Each diagonal divides it into two congruent triangles. The opposite sides and angles of a parallelogram are equal. The diagonals of a parallelogram bisect each other. Rectangle - a parallelogram in which all four angles are right angles is a rectangle. Important points -