fomulas for finding area, perimeter and volume of geometrical figures

1. GEOMETRYCAL FIGURES

3. 1.CIRCLES
“Circles are the locus of points with equal
distance from the fixed point”

4. If the radiuse of a circle is ‘r’ then
Area of a circle = ∏r2
Perimeter of a circle = 2Π r

5. 2.TRIANGLES
Triangles are the three sided closed polygon
having 3 angles

6. If the sides of a triangle is ‘a’ , ‘b’ , ‘c’ and the
height is ‘h’ then
The area of the triangle = 1/2 x base x height (1/2xbxh)
The perimeter of the triangle = a +b + c

7. 3.RECTANGLES
Rectangles are the four sided polygon having 4
angles

8. If the length and breadth is ‘a’ and ‘b’ respectively
then
The area of a rectangle = a x b
The perimeter of rectangle = 2( a+b )

9. 4. SQUARES
Squares are the four sided polygon having 4
angles

10. If the sides of a square is ‘a’ then
The area of a square = a2
The perimeter of a square = 4a

11. 5. SPHERE
A 3-dimensional object shaped like a ball.
Every point on the surface is the same distance from the center.

12. If the radius of the sphere is ‘ r ’ then
Surface Area of a sphere = 4 × π × r2
Volume of a sphere = (4/3) × π × r3

13. 6. CYLINDERS
• two identical flat ends that are circular or elliptical
• and one curved side.
It has the same cross-section from one end to the other

14. Surface Area of a Cylinder
h –height
r-radius
Surface Area = 2 × π × r × (r + h)
Which is made up of:
Surface Area of One End = π × r2
Surface Area of Side = 2 × π × r × h