A quadrilateral is a 2-dimensional closed shape with four straight sides. E.g. The shape ABCD shown here is a quadrilateral.

A line segment drawn from one vertex of a quadrilateral to the opposite vertex is called a diagonal of the quadrilateral. AC is a diagonal of quadrilateral ABCD, so is BD.

TYPES & PROPERTIES OF QUADRILATERALS

There are seven types of quadrilaterals that can be divided into two groups: parallelograms and other quadrilaterals.

1. Parallelograms

Quadrilaterals are called parallelograms if both pairs of opposite sides are equal and parallel to each other. Different parallelograms and their properties.

a) Parallelogram
Opposite sides of a parallelogram are parallel and equal in length. Opposite angles are equal in size.

b) Rectangle
Opposite sides of a rectangle are parallel and equal in length, All angles are equal to 90°.

c) Square
Opposite sides of a square are parallel and all sides are equal in length, All angles are equal to 90°.

d) Rhombus
All sides of a rhombus are equal in length,
Opposite sides are parallel,
Opposite angles of a rhombus are equal,
The diagonals of a rhombus bisect each other at right angles.

Rectangles, squares and rhombuses are parallelograms.

2.Other Quadrilaterals

Other quadrilaterals include trapeziums, kites and irregular quadrilaterals.

a) Trapezium
A trapezium has one pair of opposite sides parallel.
A regular trapezium has non-parallel sides equal and its base angles are equal.

b) Kite
Two pairs of adjacent sides of a kite are equal in length
One pair of opposite angles are equal in size.
One diagonal bisects the other.
Diagonals intersect at right angles.

3. Irregular Quadrilateral

An irregular quadrilateral does not have any special properties.

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QUADRILATERALS – Quadrilateral is a union of four line segments determined by four distinct co-planar points of which no three are collinear and the line-segment intersect at end points.
Quadrilateral ABCD is denoted by □ABCD.
PARTS OF QUADRILATERAL: (□ABCD)
Points A, B, C, D are called the vertices of □ABCD
AB, BC, CD and AD are called the sides of ABCD
AC, BD are called...

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*4 sides
* Sum of interior and exterior angles is 360®
Parallelogram
Kite
Trapezoid
1. Oppositesides are parallel
1. Two pairs of consecutive sides congruent
1. One pair of parallel sides
2. Oppositesides are congruent
2. Diagonals are perpendicular
2. Consecutive angles are
supplementary
3. Opposite angles are congruent
3. One...

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IMPORTANT TERMS, DEFINITIONS AND RESULTS
l l
Sum of the angles of a quadrilateral is 360°. A diagonal of a parallelogram divides it into two congruent triangles. In a parallelogram, (i) oppositesides are equal (ii) opposite angles are equal (iii) diagonals bisect each other A quadrilateral is a parallelogram, if (i)...

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The quadrilateral is a very interesting concept for it is rich in content and applications. Quadrilaterals such as the golden rectangle and cyclic quadrilateral are famous for their intricate properties. In high schools, however, this concept is not given emphasis and teachers are confined within the types of quadrilaterals enumerated in the textbook. In effect, students’ learning is shallow. Their interests are not...

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Golden Quadrilateral
From Wikipedia, the free encyclopedia
Golden Quadrilateral |
Highway map of India with the Golden Quadrilateral highlighted in solid blue colour |
Route information |
Maintained by NHAI |
Length: | 5,846 km (3,633 mi) |
Delhi – Kolkata |
Length: | 1,453 km (903 mi) |
Major
junctions: | NH 2 |
Delhi – Mumbai |
Length: | 1,419 km (882 mi) |
Major...

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Euthanasia is a relatively touchy subject and everyone has their own opinion on it. For me, I am pro-euthanasia and I believe that an individual’s right to autonomy and freedom of choice, euthanasia should be legalized in all the states. It is only fair to give someone that right because death is a private matter and should not be controlled by others.
If a person autonomously chooses to end his or her life or have someone else assist them in doing so, it should be allowed. One...

...[pic]
A parallelogram is a quadrilateral in which pairs of oppositesides are parallel and are congruent.
Oppositesides are parallel and equal in length, and opposite angles are equal (angles "a" are the same, and angles "b" are the same)
NOTE: Squares, Rectangles and Rhombuses are all Parallelograms!
Name the kind of parallelogram this figure displays?...

...8th QUADRILATERAL AND PARALLELOGRAM
1. Prove that in a parallelogram, the oppositesides are equal and the
opposite angles are equal.
2. Prove that diagonals of a rhombus bisect each other at right
angles.
3. Two adjacent angles of a parallelogram are as 2:3. Find the
measure of each of its angles.
4. Prove that the diagonals of a square are equal and bisect each other
at right angles....