---
title: "Lines of symmetry in 2-D shapes"
description: "Identify lines of symmetry in 2-D shapes presented in different orientations; recognise line-symmetric figures and draw lines of symmetry"
canonical: https://lightmysky.com/learn/mathematics/lines-of-symmetry-in-2-d-shapes-mt_hRZyKvz1KN
source: https://lightmysky.com/learn/mathematics/lines-of-symmetry-in-2-d-shapes-mt_hRZyKvz1KN.md
retrieved: 2026-09-02
---

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# Lines of symmetry in 2-D shapes

Identify lines of symmetry in 2-D shapes presented in different orientations; recognise line-symmetric figures and draw lines of symmetry

Subject: Mathematics · Area: Geometry · Ages 8 to 10
Page: https://lightmysky.com/learn/mathematics/lines-of-symmetry-in-2-d-shapes-mt_hRZyKvz1KN

## Ready when they can

- Find all lines of symmetry in a rectangle, square, and equilateral triangle
- Determine whether a given shape has a line of symmetry when rotated
- Identify which shapes in a set have exactly one line of symmetry
- Determine how many lines of symmetry a regular hexagon has
- Draw all lines of symmetry for a given figure
- Identify which figures from a set are not line-symmetric

## Lesson: Lines of symmetry

A line of symmetry is a fold line. Fold a shape exactly on that line, and both halves land right on top of each other and match perfectly. To find every line, try folding in as many directions as you can: up and down, side to side, and both diagonals. Draw in only the folds where both halves match.

*(drawing: A square has 4 lines of symmetry: 2 straight through the middle of each side, and 2 through opposite corners.)*

**Example.** Fold a square straight down the middle, then side to side. Both halves match. Fold it corner to corner, both ways, and those match too. That makes 4 lines of symmetry on a square.

**Example.** A rectangle that is not a square has only 2 lines of symmetry, straight through the middles of its sides. Its corner-to-corner lines do not match, so they don't count. An equilateral triangle, with all three sides the same length, has 3 lines of symmetry, one running from each corner to the middle of the opposite side.

A regular shape has every side the same length, and it gets one line of symmetry for each side. A regular hexagon has 6 equal sides, so it has 6 lines: 3 join opposite corners, and 3 join the middles of opposite sides.

Some shapes have exactly one line. A kite folds evenly straight down its middle, and no other fold works on it. Some shapes have none at all. A triangle with three different side lengths has no fold anywhere that makes the two halves match.

Turning a shape does not change how many lines of symmetry it has. Stand a square up on one corner so it looks like a diamond. It still has 4 lines of symmetry. Two of them just look diagonal now instead of straight up and down.

**Recap.** A line of symmetry is a fold line where both halves match exactly, and turning the shape never changes how many it has.

## Practice

8 questions on this page, each with its working shown.

## Needs first

- [2-D shapes (age 6+)](https://lightmysky.com/learn/mathematics/2-d-shapes-age-6-mt_sBcRdUfAzV)
- [Transformations on a grid](https://lightmysky.com/learn/mathematics/transformations-on-a-grid-mt_SH7QgFl8-v)

## Opens up

- [Lines of symmetry](https://lightmysky.com/learn/mathematics/lines-of-symmetry-mt_hR2Y7NhMSY)