Area and Perimeter

1. AREA AND PERIMETER
BY:
F.JHANSI RANI

2. AREA:
 The area is the region bounded by the shape of an object.
 The space covered by the figure or any two-dimensional
geometric shape, in a plane, is the area of the shape.
 The area of all the shapes depends upon their dimensions
and properties.

3. PERIMETER:
 Perimeter of a shape is defined as the total distance around the shape.
 Basically, perimeter is the length of any shape if it is expanded in a linear form.

4. CALCULATINGAREAANDPERIMETERFORDIFFERENTSHAPES:
TRIANGLE:
The formulas for calculating the perimeter and area of a triangle ABC are:
Perimeter and Area of a triangle
 Perimeter = a + b + c
⇒ Perimeter = sum of the length of all sides
⇒ Perimeter = a + b + c units
 Area = 1⁄2 × base × height sq.units

5. • SQUARE:
Perimeter and Area of a Square
 Perimeter = 4a
⇒ Perimeter = sum of lengths of all sides
⇒ Perimeter = a + a + a + a
⇒ Perimeter = 4a units
 Area = a2
⇒ Area = length × breadth
⇒ Area = a × a
⇒ Area = a2

6. RECTANGLE
Perimeter and Area of a Rectangle
Perimeter = 2 (l + b)
⇒ Perimeter = sum of lengths of all sides
⇒ Perimeter = l + b + l + b
⇒ Perimeter = 2 × (l + b) units
Area = l × b
⇒ Area = Area (ABC) + Area (ADC)
⇒ Area = 2 × Area (ABC)
⇒ Area = 2 × (1⁄2 × base × height)
⇒ Area = base × height
⇒ Area = l × b sq. units

7. PARALLELOGRAM:
Perimeter and Area of Parallelogram:
Perimeter of a parallelogram (P) = 2 (sum of the adjacent sides
= 2 × a + b units
Area of a parallelogram (A) = base × height
= b × h sq.units

9. EXAMPLE1:
If the radius of a circle is 21cm. Find its area and circumference.
Solution:
Given, radius = 21cm
Therefore, Area = π × r2
A = 22/7 × 21 × 21
A = 1386 sq.cm.
Circumference, C = 2πr
C = 2 x 22/7 x 21
= 132 cm

10. EXAMPLE2:
If the length of the side of a square is 11cm. Then find its area and also find the total length of its boundary.
Solution:
Given, length of the side, a = 11 cm
Area = a2 = 121 sq.cm
Total length of its boundary, Perimeter = 4a = 4 x 11 = 44 sq.cm.
Example 3:
The length of rectangular field is 12m and width is 10m. Find the area of the field along with its perimeter.
Solution:
Given, Length = 12m
Width = 10m
Therefore, Area = length x width = 12 x 10 = 120 sq.m
Perimeter = 2 (length + width) = 2 x (12 + 10) = 2 x 22 = 44 m.

11. EXAMPLE:4
Find the perimeter of a parallelogram whose adjacent sides are 5 units and 9 units.
Solution:
The adjacent sides of the given parallelogram are,
a = 5 units and b = 9 units.
Then its perimeter (P) is,
P = 2 (a + b)
P = 2 (5 + 9)
= 2 (14)
= 28 units.

12. THANK YOU