Page 210 - ICSE Math 7

3. Plot points A(5, 3) and B(2, 0) on a graph paper. Join A and B and plot the reflection of this line
segment in y-axis.
4. Plot the reflection of the following points in x-axis and y-axis.

Y Y
5 5
4 4
3 3
A(–2, 2) 2 2
1 X 1 P(4, 1)
(a) X' O (b) X' O X
–5 –4 –3 –2 –1 1 2 3 4 5 –5 –4 –3 –2 –1 1 2 3 4 5
–1 –1
–2 –2
–3 –3
–4 –4
–5 –5
Y' Y'
5. What is the order of rotational symmetry of an equilateral triangle about its centroid?

6. Find the order of rotational symmetry of the following figures about point O.

(a) O (b) O (c) O (d) O

7. For each figure given below, find the number of lines of symmetry and also the angle of rotational
symmetry about the point marked on the figure.

(a) (b) (c) (d)

8. Consider the given patterns shown below.

(a)
O

(b)
O

Which of them have:
(i) symmetry about a vertical line passing through O?
(ii) symmetry about a horizontal line passing through O?

(iii) rotational symmetry about O?

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