Quadrilaterals

Quadrilaterals

We know that a quadrilateral is a four sided polygon. We can differentiate quadrilaterals based upon the sides and the angles between sides. A quadrilateral with a pair of opposite sides parallel is called a trapezium. If the non parallel sides of the trapezium have the same length, then the trapezium is called an isosceles trapezium. A quadrilateral having exactly two distinct consecutive pairs of sides of equal length is called kite. A quadrilateral with opposite sides parallel and equal to each other is called a parallelogram.   Elements of a Parallelogram: In a Parallelogram The sides which have a common vertex are called adjacent sides. Angles having one arm in common are called adjacent angles. Angles at the opposite vertices are called opposite angles. The lines joining the opposite vertices of the parallelogram are called diagonals. The diagonals of a parallelogram are not equal. Property: The opposite sides of a parallelogram are equal.

Property: The opposite angles of a parallelogram are of equal measure. Property: The diagonals of a parallelogram bisect each other.