RS Agarwal Solution | Class 6th | Chapter-20 | Two-Dimensional Reflection Symmetry (Linear Symmetry) | Edugrown

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Exercise 20A

Question 1:

Mark (✓) against the correct answer in each of Q.1 to Q.8.
A square has
(a) one line of symmetry
(b) two lines of symmetry
(c) three lines of symmetry
(d) four lines of symmetry

ANSWER:

A square has four lines of symmetry. Hence, the correct answer is option (d).

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Question 2:

Mark (✓) against the correct answer in each of Q.1 to Q.8.
A rectangle is symmetrical about
(a) each one of its sides
(b) each one of its diagonals
(c) a line joining the midpoints of its opposite sides
(d) none of these

ANSWER:

(c) a line joining the midpoints of its opposite sides

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Question 3:

Mark (✓) against the correct answer in each of Q.1 to Q.8.
A rhombus is symmetrical about
(a) the line joining the midpoints of its opposite sides
(b) each of its diagonals
(c) perpendicular bisector of each of its sides
(d) none of these

ANSWER:

(b) each of its diagonals

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Question 4:

Mark (✓) against the correct answer in each of Q.1 to Q.8.
A circle has
(a) no line of symmetry
(b) one line of symmetry
(c) two lines of symmetry
(d) an unlimited number of lines of symmetry

ANSWER:

(d) an unlimited number of lines of symmetry

This is because a circle has infinite number of diameters. Also, a circle is symmetrical about each of its diameter.

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Question 5:

Mark (✓) against the correct answer in each of Q.1 to Q.8.
A scalene triangle has
(a) no line of symmetry
(b) one line of symmetry
(c) two lines of symmetry
(d) three lines of symmetry

ANSWER:

(a) no line of symmetry

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Question 6:

Mark (✓) against the correct answer in each of Q.1 to Q.8.
ABCD is a kite in which AB = AD and BC = DC.
The kite is symmetrical about
(a) the diagonal AC
(b) the diagonal BD
(c) none of these
Figure

ANSWER:

(a) the diagonal AC

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Question 7:

Mark (✓) against the correct answer in each of Q.1 to Q.8.
The letter O of the English alphabet has
(a) no line of symmetry
(b) one line of symmetry
(c) two lines of symmetry
(d) none of these

ANSWER:

(c) two lines of symmetry

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Question 8:

Mark (✓) against the correct answer in each of Q.1 to Q.8.
The letter Z of the English alphabet has
(a) no line of symmetry
(b) one line of symmetry
(c) two lines of symmetry
(d) none of these

ANSWER:

(a) no line of symmetry

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Question 9:

Mark (✓) against the correct answer in each of Q.1 to Q.8.
Draw the line (or lines) of symmetry of each of the following figures.
Figure

ANSWER:

(i)


(ii)


(iii)

(iv)

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Question 10:

Mark (✓) against the correct answer in each of Q.1 to Q.8.
Which of the following statements are true and which are false?
(i) A parallelogram has no line of symmetry.
(ii) An angle with equal arms has its bisector as the line of symmetry.
(iii) An equilateral triangle has three lines of symmetry.
(iv) A rhombus has four lines of symmetry.
(v) A square has four lines of symmetry.
(vi) A rectanle has two lines of symmetry.
(vii) Each one of the letters H, I, O, X of the English alphabet has two lines of symmetry.

ANSWER:

(i)   True

(ii)  True

(iii) True
An equilateral triangle is symmetrical about each one of the bisectors of its interior angle. Also, it has three bisectors.

(iv) False
A rhombus has two lines of symmetry. It is symmetrical about each one of its diagonals.

(v)  True
A square is symmetrical about each one of its diagonals and the lines joining the midpoints of the opposite sides.

(vi) True
A rectangle is symmetrical about the lines joining the midpoints of the opposite sides.

(vii) True