Quadrilaterals JEE NOTES all types of quadrilaterals with sides, angles, and diagonals labelled

What is a Quadrilateral?

• A quadrilateral is a closed figure with four sides and four angles.

• The sum of all angles in a quadrilateral is always 360°.

2. Types of Quadrilaterals (Based on Sides and Angles)

1. Square

   • All four sides equal

   • All angles are 90°

   • Opposite sides are parallel

2. Rectangle

   • Opposite sides are equal and parallel

   • All angles are 90°

3. Rhombus

   • All four sides equal

   • Opposite angles are equal

   • Opposite sides are parallel

4. Parallelogram

   • Opposite sides are equal and parallel

   • Opposite angles are equal

5. Trapezium

   • Only one pair of opposite sides parallel

6. Kite

   • Two pairs of adjacent sides equal

   • Diagonals intersect at right angles

3. Important Concepts

1. Diagonals: Lines joining opposite corners.

   • In a square or rectangle → diagonals are equal

   • In a rhombus → diagonals bisect each other at right angles

2. Angles:

   • Sum of interior angles = 360°

   • Opposite angles in parallelogram → equal

3. Sides:

   • Opposite sides in parallelogram, rectangle, rhombus → equal and parallel

4. Key Points for Exams

• Quadrilateral = 4 sides, 4 angles, sum of angles = 360°

• Types: Square, Rectangle, Rhombus, Parallelogram, Trapezium, Kite

• Diagonals: Important for properties of shapes

• Opposite sides and angles: parallel and/or equal in special quadrilaterals

• Understanding the difference between shapes helps in solving geometry problems