AREA OF PLANE FIGURES

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Welcome to Class !!

We are eager to have you join us !!

In today’s Basic Technology class, We will be discussing Area of Plane Figures. We hope you enjoy the class!

 

Definition of Area:

The area (A) of a closed plane figure is the region of the plane enclosed by the figure’s boundary. The area is measured in square units of length such as square centimetre (cm22) and square metre (m22).

 

	Triangle Area = ½ × b × h b = base h = vertical height			Square Area = a2 a = length of side
	Rectangle Area = w × h w = width h = height			Parallelogram Area = b × h b = base h = vertical height
	Trapezoid Area = ½(a+b) × h h = vertical height			Circle Area = π × r2 Circumference = 2 × π × r r = radius
				Sector Area = ½ × r2 × θ r = radius θ = angle in radians

 

Example: What is the area of this rectangle?

The formula is:

Area = w × h

w = width

h = height

We know w = 5 and h = 3, so:

Area = 5 × 3 = 15

Example:

What is the area of a circle where

Radius = r = 3

Area		= π × r2
		= π × 32
		= π × (3 × 3)
		= 3.14159… × 9
		= 28.27 (to 2 decimal places)

Example:

What is the area of a triangle where

Height = h = 12

Base = b = 20

Area = ½ × b × h = ½ × 20 × 12 = 120

 

 

We have come to the end of this class. We do hope you enjoyed the class?

Should you have any further question, feel free to ask in the comment section below and trust us to respond as soon as possible.

In our next class, we will be talking about Woodwork Machines. We are very much eager to meet you there.

 

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