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Cut it Out

Can you dissect an equilateral triangle into 6 smaller ones? What number of smaller equilateral triangles is it NOT possible to dissect a larger equilateral triangle into?

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Tessellating Transformations

Can you find out how the 6-triangle shape is transformed in these tessellations? Will the tessellations go on for ever? Why or why not?

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Triangular Hexagons

Investigate these hexagons drawn from different sized equilateral triangles.

Tri-five

Stage: 2 Challenge Level: Challenge Level:1

Find all the DIFFERENT shapes that can be made by joining five equilateral triangles edge to edge.

Here's an example:

1 or 2?

You might like to use this interactivity to try out your ideas. Click the red triangle to make a new triangle appear. You can move the triangles around by dragging with your mouse. If you hover your mouse over a corner, you will see a white circle where you can click to rotate the triangle.

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice. More information on many of our other activities can be found here.
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NRICH is part of the family of activities in the Millennium Mathematics Project.