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## 'Triangles All Around' printed from http://nrich.maths.org/

You might like to have a look at

Nine-Pin Triangles before trying this problem.

How many different triangles can you draw on a circular pegboard which has four equally spaced pegs?

What are the angles of each triangle?

If you have a six-peg circular pegboard, how many different triangles are possible now?

What are their angles?

How many different triangles could you draw on an eight-peg board?

Can you find the angles of each?

You may like to use the interactivity to try out your ideas.

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For printable sets of circle templates for use with this activity, please see

Printable Resources page.

Many thanks to Geoff Faux who introduced us to the merits of the 9 pin circular geoboard.

For further ideas about using geoboards in the classroom, please see Geoff's publications available through the Association of Teachers of Mathematics (search for 'geoboards').