The document Some Special Parallelograms Class 8 Notes | EduRev is a part of the Class 8 Course Class 8 Mathematics by VP Classes.

All you need of Class 8 at this link: Class 8

**SOME SPECIAL PARALLELOGRAMS****1. Rectangle**

A rectangle is a parallelogram in which each angle is a right angle.

In rectangle,

(i) The opposite sides are equal and parallel,

(ii) Opposite angles are equal,

(iii) Diagonals ae equal,

(iv) Diagonals bisect each other.**Note:** A rectangle is an equiangular figure but not an equilateral one.

**2. Rhombus **

Arhombus is a parallelogram in which all four sides are equal.

In a rhombus,

(i) Opposite sides are parallel,

(ii) All sides are equal,

(iii) Opposite angles are equal,

(iv) Diagonals bisect each other at right angles.

**3. Square **

A parallelogram having all of its sides equal and measure of each angle being 90Â°, is called a square.

In a square,

(i) All four sides are equal,

(ii) Opposite sides are parallel,

(iii) Each angle being equal to 90Â°,

(iv) The diagonals are equal,

(v) The diagonals bisect each other at right angles.**Note:** A square is an equilateral and equiangular quadrilateral. Therefore it is called a regular polygon.

**SUM OF THE MEASURES OF THE EXTERIOR ANGLES OF A POLYGON**

Whatever be the number of sides of a polygon, the sum of the measures of its exterior angles is always 360Â°.**For example:****(a)****âˆ ****a + âˆ b + âˆ c + âˆ d + âˆ e = 360Â°**

**(b)****âˆ ****a + âˆ b + âˆ c + âˆ d + âˆ e + âˆ f = 360Â°**

âˆµ Sum of all the exterior angles of a quadrilateral = 360Â°

âˆ´ x + 65Â° + 115Â° + 110Â° = 360Â°

or

x + 290Â° = 360Â°

or

x = 360Â° â€“ 290Â° = 70Â°

93 docs|16 tests

### Understanding Quadrilaterals - MCQ

- Test | 10 ques | 10 min