1. Which of the following dotted lines is the line of symmetry for the given figure?
a) A
b) B
c) C
d) D
Answer: c) C
Explanation: C is the line of symmetry that divides into two perfectly identical halves.
2. How many more lines of symmetry does Figure (II) have than Figure (I)?
a) 0
b) 1
c) 2
d) 3
Answer: a) 0
Explanation:
A and B are the lines of symmetry. There are two lines of symmetry in Figure (I).
P and Q are the lines of symmetry. There are two lines of symmetry in Figure (II).
They have an equal number of lines of symmetry. Hence, their difference is zero.
3. What is the least number of squares that must be added so that the line PQ becomes a line of symmetry?
a) 4
b) 5
c) 6
d) 9
Answer: b) 5
Explanation: Number of squares that must be added so that the line PQ becomes a line of symmetry is shown as.
The least number of squares that must be added so that the line PQ becomes a line of symmetry is 5.
4. What is the rotational symmetry of a figure when the object is placed at one of the vertices of an equilateral triangle?
a) 0
b) 1
c) 2
d) 3
Answer: d) 3
Explanation: The order of rotational symmetry of an equilateral triangle is 3 and its angle of rotation is 120° which is shown as:
5. Which of the following figures are symmetric?
a) Only (1), (2), (4) and (6)
b) Only (1), (3), (4) and (6)
c) Only (1), (3), (5) and (6)
d) Only (2), (3), (4) and (6)
Answer: b) Only (1), (3), (4) and (6)
Explanation: Only (1), (3), (4) and (6) are symmetric figures which are shown as:
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