Now, make your designs. Sort your designs in 3 categories—designs with only rotational symmetry, designs with only reflection symmetry, and designs with both rotational and reflection symmetry.
(1) Designs with only rotational symmetry: Shapes arranged around a centre point that look the same after rotation but have no mirror image halves. Example: a pinwheel with asymmetric blades.
(2) Designs with only reflection symmetry: Shapes with at least one line of symmetry but no rotational symmetry. Example: letter E, letter T.
(3) Designs with both symmetries: Shapes with lines of symmetry AND rotational symmetry. Example: squares, letter X, letter H.
Explanation
The chapter encourages students to create and categorize their own designs. This activity reinforces understanding of both types of symmetry. Students learn that some shapes have only one type of symmetry, while others have both. The categorization helps students distinguish between the two symmetry concepts.
Solution Steps
Create designs using shapes and patterns.
Identify designs with only rotational symmetry (no mirror lines).
Identify designs with only reflection symmetry (no rotational symmetry).
Identify designs with both rotational and reflection symmetry.