Page 24 - CITS - WCS - Mechanical

WORKSHOP CALCULATION - CITS

EXERCISE 5 : Mensuration 2D & 3D

Mensuration 2D: Concept on Basic Geometrical Definitions: The different types of shapes in geometry help
us to understand the shapes day to day life. With the help of geometric concepts, we can calculate the area,
perimeter and volume of shapes. The basic geometry is based on points, lines and planes explained in coordinate
geometry.
Two Dimensional Shapes

Ex) (x-2) =4 Ex) (x- + 3x - 4 = 0
2
2
x 2 - 4x + 4 = 4 (x - 4) (x - 1) = 0
x 2 - 4x = 0 Equation is now in x - 4 = 0 x - 1 = 0
standard form or
x(x-4) = 0 x=-4) = x = 1
x=0 x=4 Answer: x=-4, x=1
Answer: x=0, x=4
Three Dimensional Shapes (Sphere Cube Cuboids Cone Cylinder)

Triangle Circle Semi-Circle Square Rectangle Parallelogram Rhombus Trapezium Kite Polygons (Pentagon,
Hexagon, Octagon, Nonagon, Decagon, etc.)
Basic geometrical theorems

The geometry theorems are: Isosceles Triangle Theorem, Equilateral Triangle Theorem, Angle Sum Triangle
Theorem, Supplementary Angle Theorem, Opposite Angle Theorem, 3 Parallel Line Theorems, Complementary
Angle Theorem, Exterior Angle Theorem, Exterior Angles of a Polygon and Interior Angles of a Polygon.

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