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Mind Map
math Creative Thinking
GEOMETRy

Basic Geometrical Ideas Types of Lines

Point: A small dot that represents the position or location is called a point.
A Vertical Slanting
Point A Horizontal line line
Line: A path that can extend in both directions indefinitely is called a line. line
A B
Intersecting Lines
Line segment: A line segment is a part of a line. It has two end points.
A B l m

Ray: A part of a line extending only in one direction is called a ray. O
A B

Angle Parallel Lines:

When two rays or straight lines meet or intersect A p
at a point, they form an angle, as shown Arm q
alongside.
Angle Perpendicular Lines:
O B
Vertex Arm
Right
D A P Angle

E F B C Q R
Acute angle Right angle Obtuse angle

Open and Closed Figures Circle
Open figures Centre of circle
O is the centre. The distance between point O
and any point on the boundary of the circle is
equal.
Closed figures Diameter
O The diameter AB is the distance across a
A B circle through its centre.
Radius
Polygons The radius OR is the distance from the
centre to any point on the circle.
Circumference
R The circumference is the distance around
the circle.

Solids Nets of Solids
Basic Solids

Cube Cuboid
Cube Cuboid Cone Cylinder Sphere

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