Question

9.
line
point
rotational
none

10.
line
point
rotational
none

11.
line
point
rotational
none

12.
line
point
rotational
none

13.
line
point
rotational
none

14.
line
point
rotational
none

15.
line
point
rotational
none

16.
line
point
rotational
none

17.
line
point
rotational
none

18.
line
point
rotational
none

19.
line
point
rotational
none

20.
line
point
rotational
none

Explanation:

Analyze symmetry types for questions 9 to 12

Using the Line Symmetry, Point Symmetry, and Rotational Symmetry knowledge points

• Question 9 (Pinwheel): Rotates onto itself by \(90^\circ\). No reflection lines. Center is not a point of symmetry because it lacks \(180^\circ\) rotational symmetry (it has 4-fold pinwheel chirality). Thus, it has Rotational symmetry only.
• Question 10 (Hourglass/Double Cup): Has a vertical line of reflection and a horizontal line of reflection (Line). It maps onto itself when rotated \(180^\circ\) (Rotational and Point).
• Question 11 (Letter R): Asymmetric. No lines of reflection, no rotational symmetry. Thus, None.
• Question 12 (Rhombus): Has vertical and horizontal lines of reflection (Line). It maps onto itself when rotated \(180^\circ\) (Rotational and Point).

Analyze symmetry types for questions 13 to 16

Using the Line Symmetry, Point Symmetry, and Rotational Symmetry knowledge points

• Question 13 (Three-leaf clover/Triquetra): Has 3 lines of reflection passing through each leaf (Line). Rotates onto itself by \(120^\circ\) (Rotational). No point symmetry.
• Question 14 (Letter Z): No lines of reflection. Rotates onto itself by \(180^\circ\) (Rotational and Point).
• Question 15 (Four-leaf clover): Has 4 lines of reflection (Line). Rotates onto itself by \(90^\circ\) and \(180^\circ\) (Rotational and Point).
• Question 16 (Queen of Spades playing card): Standard playing cards are designed with two-fold rotational symmetry so they look the same upside down. Rotates by \(180^\circ\) (Rotational and Point). No reflection lines due to the layout of the suit symbols and queen's portrait.

Analyze symmetry types for questions 17 to 20

Using the Line Symmetry, Point Symmetry, and Rotational Symmetry knowledge points

• Question 17 (L-bracket/Chevron): Has 1 diagonal line of reflection (Line). No rotational or point symmetry.
• Question 18 (Crescent): Has 1 horizontal line of reflection (Line). No rotational or point symmetry.
• Question 19 (Recycling symbol): Has 3-fold rotational symmetry (\(120^\circ\)) (Rotational). No reflection lines due to the overlapping directional arrows.
• Question 20 (Snowflake): Has 6 lines of reflection (Line). Rotates onto itself by \(60^\circ\) (Rotational and Point).

Answer:

No.	Answer
10	Line, Point, Rotational
11	None
12	Line, Point, Rotational
13	Line, Rotational
14	Point, Rotational
15	Line, Point, Rotational
16	Point, Rotational
17	Line
18	Line
19	Rotational
20	Line, Point, Rotational