Illuminations: Symmetries II

# Symmetries II

This is the second i-Math in a four-part series of i-Maths entitled Symmetries and Their Properties. In this second i-Math you will investigate reflection, mirror, or bilateral symmetry. Mirrors can be used to create reflection symmetry. Many objects in nature, such as butterflies, the human body, and many types of leaves have bilateral symmetry. Objects we use every day, such as spoons, chairs, and cars also have bilateral symmetry. In this i-Math, you will learn about the mathematical properties of mirror symmetry and have a chance to create designs with mirror symmetry.

### Math Content

This is the second i-Math in a four-part series of i-Maths entitled Symmetries and Their Properties. In this second i-Math you will investigate reflection, mirror, or bilateral symmetry.

### Individual Lessons

Lesson 1 - Describing Reflections

This investigation will help you to understand how reflections work and what happens when two or more reflections are applied one after the other.

Lesson 2 - Relationships Between Reflections and Symmetry

Many patterns and designs have bilateral symmetry. In this part, you will learn the properties of designs that have this kind of symmetry.

Lesson 3 - Reflections Across Two Mirror Lines

In this section, you will learn what happens when a design is reflected twice across two different mirror lines.

Lesson 4 - Conclusions

In this part, you will take stock of what you have learned about reflections.

### NCTM Resources

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