Download - BASICS OF QUADRILATERALS
Quadrilateral – The word ‘quad’ means four and the word ‘lateral’ means
sides.
- It is a figure bounded by four line segments such that
no three of them are parallel to each other
- It has four sides, vertices, and angles
SOME IMPORTANT DEFINITIONS:-
a) Adjacent sides- also known as consecutive sides
- two sides of quadrilateral with common vertex
b) Opposite sides- two sides of quadrilateral with no common end- point
c) Adjacent angles- also known as consecutive angles
- two angles of a quadrilateral with common arm
d) Opposite angles- two angles of a quadrilateral with no common arm
Trapezium Kite
Rhombus Square
Parallelogram Rectangle
Types of Quadrilaterals
Let us discuss about various kinds of quadrilaterals briefly:-
TRAPEZIUM A quadrilateral with one pair of parallel sides
ISOSCELES TRAPEZIUM A trapezium with non parallel sides as equal
TRAPEZIUM ISOSCELES TRAPEZIUM
PARALLELOGRAM A quadrilateral with both pairs of opposite sides equal
RHOMBUS A parallelogram with all sides equal
RECTANGLE A parallelogram whose each angle is right angle
SQUARE A rectangle with pair of adjacent sides equal
KITE A quadrilateral with two pairs of equal adjacent sides and unequal
opposite sides
Let us discuss about various types of quadrilaterals in detail !!!
*RECTANGLE opposite sides are parallel and equal
all angles are right angles
diagonals are equal
diagonals bisect each other
*SQUARE all sides are equal
all angles are right angles
opposite sides are parallel
diagonals are equal
diagonals bisect each other at right angles
diagonals are perpendicular to each other
*RHOMBUS opposite sides are parallel
all sides are equal
opposite angles are equal
diagonals bisect each other
diagonals are perpendicular to each other
*KITE two pairs of equal adjacent sides
*PARALLELOGRAM opposite sides are equal
opposite angles are equal
diagonals bisect each other
diagonals divide it into two congruent triangles
bisect of any two consecutive angles intersect at right
angle
its angle bisectors form a rectangle
*TRAPEZIUM one pair of opposite sides are parallel
(Isosceles Trapezium has non- parallel sides equal to each other)
ANGLE SAUM PROPERTY OF A QUADRILATERAL
This property states that sum of four angles of a quadrilateral is 360
SUBJECT – Maths
CLASS – IX
CHAPTER – Quadrilaterals
GROUP MEMBERS – Ankita, Jeetin, Kamlesh, Shikha, Radhika, Surbhi,
Zenul
SUBMITTED ON – 22.11.2013
GROUP ACTIVITY OF CLASS IX