Ncert Solutions For Class 7 Maths Ex 14.1

Ncert Solutions For Class 7 Maths Chapter 14 Ex 14.1

Q.1. Copy the figures with punched holes and find the axes of symmetry for the following:

1

Solution:

1.

2

2.

3

3.

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4.

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5.

6

6.

8

7.

9

8.

10

9.

11

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12

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12.

14

 

 

Q.2. Express the following in exponential form:

 15

Solution:

 16

 

 

Q.3. In the following figures, the mirror line (i.e., the line of symmetry) is given as a dotted line. Complete each figure performing reflection in the dotted (mirror) line. (You might perhaps place a mirror along the dotted line and look into the mirror for the image). Are you able to recall the name of the figure you complete?

 17

Solution:

 18

 

Q.4. Identify multiple lines of symmetry, if any, in each of the following figures:

 19

 

Solution:

20

 

Q.5. Copy the figure given here: Take any one diagonal as a line of symmetry and shade a few more squares to make the figure symmetric about a diagonal. Is there more than one way to do that? Is the figure symmetric if using both diagonals as lines of symmetry?

21

Solution:

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Yes, there is more than one way. Yes, this figure will be symmetric using both the diagonals.

 

Q.6. Copy the diagram and complete each shape to be symmetric about the mirror line(s):

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Solution:

24

 

Q.7. State the number of lines of symmetry for the following figures:

(I) An equilateral triangle

(II) An isosceles triangle

(III) A scalene triangle

(IV) A square

(V) A rectangle

(VI) A rhombus

(VII) A parallelogram

(VIII) A quadrilateral

(IX) A regular hexagon

(X) A circle

Solution:

25

 

Q.8. What letters of the English alphabet have reflectional symmetry (i.e., symmetry related to mirror reflection) about.

(a) a vertical mirror

(b) a horizontal mirror

(c) both horizontal and vertical mirrors

Solution:

(a) Vertical mirror – A, H, I, M, O, T, U, V, W, X and Y

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(b) Horizontal mirror – B, C, D, E, H, I, O and X

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(c) Both horizontal and vertical mirror – H, I, O and X

 

Q.9. Give three examples of shapes with no line of symmetry.

Solution: The three examples are:

(i)Quadrilateral

(ii)Scalene triangle

(iii)Parallelogram

 

Q.10. What other name can you give to the line of symmetry of:

 (a) an isosceles triangle?

 (b) a circle?

Solution:

(a) The line of symmetry of an isosceles triangle is median or altitude.

(b) The line of symmetry of a circle is diameter.

 

Class 7th

Chapter-14

Symmetry