AP State Syllabus AP Board 7th Class Maths Solutions Chapter 15 Symmetry InText Questions and Answers.

## AP State Syllabus 7th Class Maths Solutions 15th Lesson Chapter 15 Symmetry InText Questions

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Question 1.

What is the angle of rotational symmetry of a square ? (Page No. 285)

Solution:

90°

Question 2.

What is the angle of rotational symmetry of a parallelogram ? (Page No. 285)

Solution:

180°

Question 3.

What is the angle of rotational symmetry of a circle ? (Page No. 285)

Solution:

The circle can be rotated through any angle to get rotational symmetry.

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Question 1.

Name a few things in nature, that are symmetric. (Page No. 278)

Solution:

The things which have symmetry in nature are

- An apple.
- The Moon, the Sun and the Earth.
- Head (face) of a tiger.
- A human being face.
- A rose flower.

Question 2.

Name 5 man made things that are symmetric. (Page No. 278)

Solution:

- Awheel.
- Square shaped cake.
- A tube.
- A Maths textbook.
- A Cricket ball.

Question 3.

i) Can you now tell the order of rotational symmetry for an equilateral triangle. (Page No. 285)

ii) How many lines of symmetry ?

iii) What is the angle between every adjacent axes ?

Solution:

i) Order of rotational symmetry for an equilateral triangle = 120°

ii) 3 lines.

iii)120°

Question 4.

Look around you. Name five objects which have rotational symmetry (i.e rational symmetry of order more than 1). (Page No. 285)

Solution:

Circle, wheel, square etc.

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Question 1.

Can we make a polygon with less than three line segments ? (Page No. 279)

Solution:

No. We can t make a polygon with less than three line segments.

Question 2.

What is the minimum number of sides of a polygon ? (Page No. 279)

Solution:

Minimum number of sides of a polygon is 3.

Question 3.

Given below are three types of triangles. Do all the triangles have the same number of lines of symmetry ? Which triangles has more ? (Page No. 279)

Solution:

An equilateral triangle has more number of lines of symmetry.

Question 4.

Given below are different types of quadrilaterals. Do all of them have the same number of lines of symmetry ? Which quadrilateral has the most ? (Page No. 281)

Solution:

By folding also we conclude that a regular polygon has the maximum number of lines / axes of symmetry.

In the above case a square has maximum number of axes of symmetry.

All of them do not have the same number of axes of symmetry.