rectangular in shape may be used as an example with the border strip indicating the
pathways.
- 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.
- 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