Lines of Symmetry Worksheet

Lines of symmetry at a glance

A shape has a line of symmetry if a line can be drawn through the shape so that each half of the shape is an exact mirror image of the other half (identical halves). Some 2D shapes have multiple lines of symmetry, some have one and others don’t have any.

We might be asked to draw lines of symmetry on different shapes or to identify the number of lines of symmetry a polygon may have. We could also be asked to create symmetrical shapes by adding sections or shading parts of a diagram. 

Regular polygons have a number of lines of symmetry equal to their number of sides. For example, an equilateral triangle has three lines of symmetry and a regular hexagon has six lines of symmetry. Drawing a symmetric figure in different orientations will not change its lines of symmetry. 

Usually diagrams are placed on grids or a set of xy axes. 

Vertical lines of symmetry can be labelled as x=a where a is an integer or a decimal.

Horizontal lines of symmetry can be labelled as y=b where b is an integer or a decimal.

Two types of shape symmetry include line symmetry and rotational symmetry.

Looking forward, students can then progress to additional symmetry worksheets and other geometry worksheets, for example a simplifying expressions worksheet or simultaneous equations worksheet.

For more teaching and learning support on Geometry our GCSE maths lessons provide step by step support for all GCSE maths concepts.