Geometry: Properties of Quadrilaterals
This is a free lesson from our course in Geometry
 
   
In this lesson you’ll learn the Properties of different types of Quadrilaterals. You’ll explore it starting from earlier learning about polygons. The quadrilaterals always have 4 sides and in broad framework there are seven types of quadrilaterals that may be divided into two major groups i.e. parallelograms and other quadrilaterals. Also the interior angles of a quadrilateral add up to 360 degrees. The properties and related details will be explained in the contents presented by the instructor in own handwriting, using video and with the help of several examples with solution.
Properties of quadrilaterals:
In a quadrilateral; if opposite sides and opposite angles are equal, it is a parallelogram.
Important Properties of parallelograms:
In a parallelogram-
• opposite sides are equal
• opposite angles are equal
• diagonals bisect each other (More text below video...)
<h2> Geometry - Properties of Quadrilaterals</h2> <p> properties, quadrilateral, video, polygon, properties of quadrilaterals, geometry, angles, number, measure, rays, sides, line, vertices, adjacent, opposite, geometry help, diagonal, endpoint, interior angle, solution, geometry tutorials, practice questions, quizzes</p> <p> A quadrilateral is a polygon with four sides and it has four vertices. Two sides of a quadrilateral, which have a common vertex, are called adjacent sides E.g. in quadrilateral ABCD, AB and BC, BC and CD, CD and DA, DA and AB are the pairs of adjacent sides.</p>
Other useful lessons:
Special Quadrilaterals
(Continued from above)
Quadrilateral
A polygon with four sides.
Parallelogram:
• Both pairs of opposite sides are parallel.
• Both pairs of opposite sides are congruent.
• One pair of opposite sides are parallel and congruent.
• Diagonals bisect each other.
• Both pairs of opposite angles are congruent.
• Consecutive angles are supplementary.
Square
• It has all the properties of a parallelogram.
• It has all the properties of a rectangle.
• It has all the properties of a rhombus.





Rectangle
• It has all the properties of a parallelogram. 
•  It has a right angle. 
•  Diagonals are congruent.







Trapezoid 
• In Trapezoid exactly one pair of opposite sides are parallel. 
• In this exactly two pairs of consecutive angles are supplementary.
Rhombus
• It has all the properties of a parallelogram. 
• It has all sides are congruent.
• Here diagonals are perpendicular.
• Diagonals bisect the opposite angles.
Kite:
• In this both pairs of consecutive sides are congruent but opposite sides are not congruent.
• It has perpendicular diagonals.
• Exactly one pair of opposite angles are congruent.
Now you can further explore and learn relationship in more details. For example,
Parallelogram:
Each pair of opposite sides is equal and parallel
In Fig-1 below,
Opposite sides: PQ || SR and PS || QR
PQ = SR and PS = QR
Opposite angles are equal
In the Fig-1 P = R and Q= S
Diagonals of a parallelogram bisect each other
In the Fig-2, OS = OQ and OP = OR
Properties of Parallelogram
Each diagonal divides the parallelogram into two congruent triangles i.e. in the Fig-2, PQS RSQ. Similarly, PQR RSP
Opposite Sides
Two sides of a quadrilateral, that have no common point, are known as opposite sides. In Fig-3, PQ and SR is one pair of opposite sides and PS and QR is the other pair of opposite sides
Consecutive sides
Two sides of a quadrilateral, that have a common end point, are known as consecutive sides. In Fig- 3, PQ and QR is one pair of consecutive sides. Then QR, RS; RS, SP; and SP, PQ are the other three pairs of consecutive sides
Opposite angles
Two angles, that do not include a side in their intersection, are known as the opposite angles of a quadrilateral. In the above figure, angle P and angle R is one pair of opposite angles, Q and S is another pair of opposite angles.
Consecutive angles
Two angles of a quadrilateral, which include a side in their intersection, are called consecutive angles. In above figure, angle P and angle Q is one pair of consecutive angles, Q,R; R,S; and S,P are the other three pairs of consecutive angles.
Remembering the properties of quadrilaterals in above table and here below will help you to apply them to solve the problems:
• A parallelogram is a quadrilateral whose opposite sides equal and parallel.
• A rectangle, a rhombus and a square are considered as parallelograms
• A trapezoid is quadrilateral with one pair of opposite sides being parallel. Thus, it is not a parallelogram.
The video above will explain more in detail about Quadrilateral properties and their relationship, with the help of several examples.
Winpossible's online math courses and tutorials have gained rapidly popularity since their launch in 2008. Over 100,000 students have benefited from Winpossible's courses... these courses in conjunction with free unlimited homework help serve as a very effective math-tutor for our students.
- All of the Winpossible math tutorials have been designed by top-notch instructors and offer a comprehensive and rigorous math review of that topic.
- We guarantee that any student who studies with Winpossible, will get a firm grasp of the associated problem-solving techniques. Each course has our instructors providing step-by-step solutions to a wide variety of problems, completely demystifying the problem-solving process!
- Winpossible courses have been used by students for help with homework and by homeschoolers.
- Several teachers use Winpossible courses at schools as a supplement for in-class instruction. They also use our course structure to develop course worksheets.
 
       
     
 Copyright © Winpossible, 2010 - 2011
Best viewed in 1024x768 & IE 5.0 or later version