OP Malhotra Notes on Area of Plane Figures Class-9 S.Chand ICSE Maths Ch-16. We Provide Step by Step Notes on Area and Perimeter of Rectangle, Square, Triangle, Trapezium and Parallelogram OP Malhotra Maths . Visit official Website CISCE  for detail information about ICSE Board Class-9.

OP Malhotra Area of Plane Figures Class-9 S.Chand ICSE Maths Ch-16

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 the Square:

● Perimeter of square = 4 × S.

● Area of square = S × S.

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

Practice Questions on Perimeter and Area of Square and Rectangle :- Exercise-16(a)

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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)

Practice Questions on Perimeter and Area of Triangle :- Exercise-16(b)

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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

Practice Questions on Area of Parallelogram and Rhombus :- Exercise-16(c)

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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.

Practice Questions on Perimeter and Area of Trapezium :- Exercise-16(d)

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In this chapter, we study all the topics on Area of Plane Figures and do some practice questions also. Here we solve extra practice questions on this chapter for better understanding.

Here is the link for extra practice questions on Area of Plane Figures :- Chapter Test

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— : End of Notes on Area of Plane Figures OP Malhotra S Chand 2026-27 :–

Return to :–   OP Malhotra S Chand Solutions for ICSE Class-9 Maths

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