Chapter 17: Symmetry Exercise 17.4

Question: 1

The total number of lines of symmetry of a scalene triangle is

(a) 1

(b) 2

(c) 3

(d) none of these

Solution:

(d) none of these

This is because the line of symmetry of a scalene triangle is 0.

 

Question: 2

The total number of lines of symmetry of an isosceles triangle is

(a) 1

(b) 2

(c) 3

(d) none of these

Solution:

(a) 1

Total number of lines of symmetry

 

Question: 3

An equilateral triangle is symmetrical about each of its

(a) altitudes

(b) median

(c) angle of bisectors

(d) all of the above

Solution:

(d) all the above

In equilateral triangle altitudes, angle bisectors and medians are all the same.

An equilateral triangle is symmetrical


Question: 4

The total number of lines of symmetry of a square is

(a) 1

(b) 2

(c) 3

(d) 4

Solution:

(d) 4

The total number of lines of symmetry


Question: 5

A rhombus is symmetrical about

(a) each of its diagonals

(b) the line joining the mid-points of its opposite sides

(c) perpendicular bisectors of each of its sides

(d) none of these

Solution:

(a)

Each of its diagonals

A rhombus is symmetrical


Question: 6

The number of lines of symmetry of a rectangle is

(a) 0

(b) 2

(c) 4

(d) 1

Solution:

(b) 2

The number of lines of symmetry of a rectangle


Question: 7

The number of lines of symmetry of a kite is

(a) 0

(b) 1

(c) 2

(d) 3

Solution:

(b) 1

The number of lines of symmetry of a kite


Question: 8

The number of lines of symmetry of a circle is

(a) 0

(b) 1

(c) 4

(d) unlimited

Solution:

(d) Unlimited

A circle has an infinite number of symmetry all along the diameters. It has an infinite number of diameters

The number of lines of symmetry of a circle

 

Question: 9

The number of lines of symmetry of a regular hexagon is

(a) 1

(b) 2

(c) 6

(d) 8

Solution:

(c) 6

The number of lines of symmetry of a regular hexagon

 

Question: 10

The number of lines of symmetry of an n – sided regular polygon is

(a) n

(b) 2n

(c) n/2

(d) none of these

Solution:

(a) n

The number of lines of symmetry of a regular polygon is equal to the sides of the polygon. If it has ‘n’ number of sides, then there are ‘n’ lines of symmetry

 

Question: 11

The number of lines of symmetry of the letter O of the English alphabet is

(a) 0

(b) 1

(c) 2

(d) 3

Solution:

(c) 2

The number of lines of symmetry of the letter O

 

Question: 12

The number of lines of symmetry of the letter Z of the English alphabet is

(a) 0

(b) 1

(c) 2

(d) 3

Solution:

(a) 0

Z has no line of symmetry