PPT: Symmetrical Designs | Mathematics (Maths Mela) Class 5 - New NCERT PDF Download

 Page 1


Symmetrical Designs
Page 2


Symmetrical Designs
What is Symmetry?
Symmetry means that when we divide a shape into two parts, both parts look the same, like a mirror image.
Two main types:
Reflection Symmetry (Mirror Symmetry) a.
Rotational Symmetry b.
Page 3


Symmetrical Designs
What is Symmetry?
Symmetry means that when we divide a shape into two parts, both parts look the same, like a mirror image.
Two main types:
Reflection Symmetry (Mirror Symmetry) a.
Rotational Symmetry b.
Reflection Symmetry
A figure has reflection symmetry if one half is the mirror image of the other.
The dividing line is called the Line of Symmetry.
When folded along this line, both halves overlap exactly.
Example: A square has 4 lines of symmetry, which are 
lines through the midpoints of opposites sides, and lines 
through opposite vertices make up the four lines of 
symmetry.
Page 4


Symmetrical Designs
What is Symmetry?
Symmetry means that when we divide a shape into two parts, both parts look the same, like a mirror image.
Two main types:
Reflection Symmetry (Mirror Symmetry) a.
Rotational Symmetry b.
Reflection Symmetry
A figure has reflection symmetry if one half is the mirror image of the other.
The dividing line is called the Line of Symmetry.
When folded along this line, both halves overlap exactly.
Example: A square has 4 lines of symmetry, which are 
lines through the midpoints of opposites sides, and lines 
through opposite vertices make up the four lines of 
symmetry.
Line of Symmetry
The line that divides a shape into two equal, mirror-image halves is called the line of symmetry.
Vertical Line of Symmetry 3 The line goes up and down.
Horizontal Line of Symmetry 3 The line goes left to right.
Some shapes have more than one line of symmetry.
Page 5


Symmetrical Designs
What is Symmetry?
Symmetry means that when we divide a shape into two parts, both parts look the same, like a mirror image.
Two main types:
Reflection Symmetry (Mirror Symmetry) a.
Rotational Symmetry b.
Reflection Symmetry
A figure has reflection symmetry if one half is the mirror image of the other.
The dividing line is called the Line of Symmetry.
When folded along this line, both halves overlap exactly.
Example: A square has 4 lines of symmetry, which are 
lines through the midpoints of opposites sides, and lines 
through opposite vertices make up the four lines of 
symmetry.
Line of Symmetry
The line that divides a shape into two equal, mirror-image halves is called the line of symmetry.
Vertical Line of Symmetry 3 The line goes up and down.
Horizontal Line of Symmetry 3 The line goes left to right.
Some shapes have more than one line of symmetry.
Reflection Symmetry in Alphabets
Some letters have 1 line of symmetry, some have 2, and some have none.
Examples:
Vertical symmetry ³ A, V, T
Horizontal symmetry ³ I, K
Both vertical & horizontal symmetry ³ O, H, X