Page 2 - LN 6.2

2
= [45 + 8 + 9] cm
=62 cm
2
 Area of triangle:

The area of triangle BAD is half of the area of the rectangle ABCD.
NOTE:

 We can estimate the area of any irregular simple closed shape by using a
sheet of squared paper or graph paper where every square measures 1

unit × 1 unit or 1 square unit. To estimate the area, we can trace the
shape onto a piece of transparent paper and place the same on a piece
of squared or graph paper and then follow the below conventions —
1. The area of one full small square of the squared or graph paper is

taken as 1 sq unit.
2. Ignore portions of the area that are less than half a square.
3. If more than half of a square is in a region, just count it as 1 sq unit.

4. If exactly half the square is counted, take its area as sq unit

 Two closed figures can have the same area with different perimeters, or
the same perimeter with different areas.
 Areas of regions can be estimated (or even determined exactly) by

breaking up such regions into unit squares, or into more general shaped
rectangles and triangles whose areas can be calculated.