Final Cover - For Printing

(singke) #1
rectangular in shape may be used as an example with the border strip indicating the
pathways.


  1. Area of a rectangle
    The product of the length and width of a rectangle is the area of the rectangle.


Therefore, area of a rectangle = length × width

In symbols, A = l X b


= lb Sq. units

Here, ‘A’ refers to the area, ‘l’ refers to the length, and ‘b’ refers to the breadth (or
width) of the rectangle.

Note :
Here, A = lb and so lb = A

Then b^ =^ Al

And also l^ =^ bA

That is, length = WidthArea

and width = LengthArea

The idea may be explained to the child by demonstration using the rectangular sheet.


  1. Area of a right angle triangle
    A right angle triangle can be obtained by cutting across the diagonal of a rectangle.
    That is a right angle triangle is one of the two identical halves of a rectangle when it
    is cut across its diagonal. Hence the area of a right triangle will be equal to one half
    of the area of the rectangle.


Thus, area of a right angle triangle = 21 × base × height
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