Line Symmetry

Line symmetry, also known as reflection symmetry, occurs when a figure can be divided into two equal halves that are mirror images of each other, with respect to a line. This line is called the line of symmetry. When the figure is folded along the line of symmetry, the two halves will perfectly coincide.

Properties of Line Symmetry

1. Every figure with line symmetry has at least one line of symmetry.
2. The line of symmetry divides the figure into two mirror-image halves.
3. A figure can have multiple lines of symmetry depending on its shape.
4. A figure can have no lines of symmetry, especially if it has irregular or asymmetrical shapes.

Identifying Line Symmetry

To identify line symmetry in a figure, you can follow these steps:

1. Draw the figure on a piece of paper.
2. Identify potential lines of symmetry, such as vertical, horizontal, or diagonal lines.
3. Test each potential line of symmetry by folding the paper along the line. If the two halves match up perfectly, that line is a line of symmetry.

Examples of Line Symmetry

Examples of figures with line symmetry include:

• Square: 4 lines of symmetry
• Rectangle: 2 lines of symmetry
• Equilateral triangle: 3 lines of symmetry
• Circle: infinite lines of symmetry (any line passing through the center)

Study Guide

Here are some key points to remember about line symmetry:

• Line symmetry occurs when a figure can be divided into two equal halves that are mirror images of each other.
• The line of symmetry is the line along which the figure can be folded to create the mirror images.
• Some figures have multiple lines of symmetry, while others have none.
• Practice identifying line symmetry in different geometric figures to deepen your understanding.