# RS Aggarwal Class-9 Perimeter and Area of Plane Figures ICSE Maths

RS Aggarwal Class-9 Perimeter and Area of Plane Figures ICSE Maths Goyal Brothers Prakashan Chapter-17. We provide step by step Solutions of Exercise / lesson-17 Perimeter and Area of Plane Figures for ICSE Class-9 RS Aggarwal Mathematics .

Our Solutions contain all type Questions with Exe-17(A), Exe-17(B), with Notes on Perimeter and Area of Plane Figures to develop skill and confidence. Visit official Website CISCE for detail information about ICSE Board Class-9 Mathematics.

## RS Aggarwal Class-9 Perimeter and Area of Plane Figures ICSE Maths Goyal Brothers Prakashan Chapter-17

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Notes on Perimeter and Area

Exe-17 (A)

Exe-17 (B) (form Q-1 to 26 )

Exercise-17 (B) (form Q-27 to 30 )

### on Perimeter and Area

#### Perimeter:

The length of the boundary of a closed figure is called the perimeter of the plane figure. The units of perimeter are same as that of length, i.e., m, cm, mm, etc

#### Area:

A part of the plane enclosed by a simple closed figure is called a plane region and the measurement of plane region enclosed is called its area.

Area is measured in square units.

The units of area and the relation between them is given below:

#### Perimeter and Area of Rectangle:

● The perimeter of rectangle = 2(l + b).

● Area of rectangle = l × b; (l and b are the length and breadth of rectangle)

● Diagonal of rectangle = √(l² + b²)

#### Perimeter and Area of the Square:

● Perimeter of square = 4 × S.

● Area of square = S × S.

● Diagonal of square = S√2; (S is the side of square)

#### Perimeter and Area of the Triangle:

• Perimeter of triangle = (a + b + c); (a, b, c are 3 sides of a triangle)
• Area of triangle = √(s(s – a) (s – b) (s – c)); (s is the semi-perimeter of triangle)
• S = 1/2 (a + b + c)
• Area of triangle = 1/2 × b × h; (b base , h height)
• Area of an equilateral triangle = (a²√3)/4; (a is the side of triangle)

#### Perimeter and Area of the Parallelogram:

• Perimeter of parallelogram = 2 (sum of adjacent sides)
• Area of parallelogram = base × height

#### Perimeter and Area of the Rhombus:

• Area of rhombus = base × height
• Area of rhombus = 1/2 × length of one diagonal × length of other diagonal
• Perimeter of rhombus = 4 × side

#### Perimeter and Area of the Trapezium:

● Area of trapezium = 1/2 (sum of parallel sides) × (perpendicular distance between them)
= 1/2 (p₁ + p₂) × h (p₁, p₂ are 2 parallel sides)

#### Circumference and Area of Circle:

● Circumference of circle = 2πr
= πd
Where, π = 3.14 or π = 22/7
r is the radius of circle
d is the diameter of circle
● Area of circle = πr²

● Area of ring = Area of outer circle – Area of inner circle.

 Shape Area Perimeter Terms Circle A = π × r2 Circumference = 2πr r = radius of the circle Triangle A = ½ × b × h S = a+b+c b = base, h = height a,b and c are the sides of the triangle Square A = a2 P = 4a a = length of side Rectangle A = l × w P = 2(l + w) l = length, w = width Parallelogram A = b × h P = 2(b + h) b=base, h=vertical height

### Exe-17 (B)  (form Q-1 to 26 )

RS Aggarwal Class-9 Perimeter and Area of Plane Figures ICSE Maths Goyal Brothers Prakashan

### Exe-17 (B)  (form Q-27 to 30)

RS Aggarwal Class-9 Perimeter and Area of Plane Figures ICSE Maths Goyal Brothers Prakashan

What is the difference between area and perimeter?

The area is the region covered by shape or figure whereas perimeter is the distance covered by outer boundary of the shape.
The unit of area is given by square unit or unit2 and unit of perimeter is same as the unit.

#### What is the formula for perimeter?

The perimeter of any polygon is equal to the sum of its sides.
Perimeter = Sum of all sides

#### What is the area and perimeter of a circle?

A circle is a curved shape and its area and perimeter are given by its radius.
Area of circle is πr2
Perimeter or circumference of circle is 2πr.

#### What is the perimeter and area example?

If a square has side length of 2cm then,
Area of square = side2 = 22 = 4cm2
Perimeter of square = sume of all sides = 2+2+2+2 = 8

#### What is the formula for area of rectangle?

The area of rectangle is equal to the product of its length and breadth.