# Math's: Meaning of Perimeter and Area: Perimeter and Area of Some Quadrilaterals

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## Meaning of Perimeter and Area

• The total length of the boundary of a closed plane figure is called its Perimeter. The perimeter is measured in some linear units such as , etc.

• The measure of the region enclosed by a plane figure is known as Area. Area is measured in square units such as , etc.

## Formula for Perimeter and Area of Some Specific Quadrilaterals and Triangles

;

Area:

;

Area:

### Triangle- Area

When altitude or height is given, then,

When altitude or height is not given then, where represents the semi perimeter and .

### Circle- Perimeter or Circumference

;

Area: where and represents the radius of the circle

### Sector- Perimeter

Area: where is the angle of the sector

### Ring or Circular Path- Perimeter

Area:

where is the radius of the larger circle and is the radius of the smaller circle.

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