Stage: 1 Challenge Level: 
You might find it useful to print off this sheet of lots of the triangles.
How do you know your design has a line of symmetry?
Have you tried using more/fewer colours?
Multiplication & division. Investigations. Equilateral triangles. Symmetry. Sequences. Combinations. Area. Addition & subtraction. Working systematically. Practical Activity.
Published April 2000,January 2009.
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