NCERT Solutions for Class 7 Maths Chapter 14 Symmetry Ex 14.3

Class 7 Maths NCERT Solutions Chapter 14 Symmetry Ex 14.3

Question 1.
Name any two figures that have both line symmetry and rotational symmetry.
Solution:

1. Circle
2. Equilateral triangle

Question 2.
Draw, wherever possible, a rough sketch of
(i) a triangle with both line and rotational symmetries of order more than 1.
Solution:
Three lines of symmetry

Also, an equilateral triangle has rotational symmetry of order 3 as shown below:

(ii) a triangle with only line symmetry and no rotational symmetry of order more than 1.
Solution:
One line of symmetry but no rotational symmetry of order more than 1.

(iii) a quadrilateral with rotational symmetry of order more than 1 but not a line symmetry.
Solution:
No line of symmetry but have rotational symmetry of order more than 1.

(iv) a quadrilateral with line symmetry but not a rotational symmetry or order more than 1.
Solution:
One line of symmetry but no rotational symmetry of order more than 1.

Question 3.
If a figure has two or more lines of symmetry, should it have rotational symmetry of order more than 1?
Solution:
When a figure has two or more lines of symmetry, then the figure should have rotational symmetry of order more than 1.

Question 4.
Fill in the blanks:

Shape	Centre of Rotation	Order of Rotation	Angle of Rotation
Square
Rectangle
Rhombus
Equilateral Triangle
Regular Hexagon
Circle
Semicircle

Solution:

Shape	Centre of Rotation	Order of Rotation	Angle of Rotation
Square	Yes	4	90°
Rectangle	Yes	4	90°
Rhombus	Yes	4	90°
Equilateral Triangle	Yes	3	120°
Regular Hexagon	Yes	6	60°
Circle	Yes	Infinite	Any angle
Semicircle	Yes	4	90°

Question 5.
Name the quadrilaterals which have both line and rotational symmetry of order more than 1.
Solution:

1. Square
2. Rectangle

Question 6.
After rotating by 60° about a center, a figure looks exactly the same as its original position. At what other angles will this happen for the figure?
Solution:
The other angles are 120°, 180°, 240°, 300°, 360°.

Question 7.
Can we have rotational symmetry of order more than 1 whose angle of rotation is

(i) 45°?
Solution:
Yes

(ii) 17°?
Solution:
No