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Triangle Edges

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Lucy from Avoca Beach, Australia wrote to say:

I made triangles using red, green and blue sticks. Red was 3cm, green was 4cm and blue was 5cm.These are all my triangles:
333 334 335 444 344 445 555 554 355 345

There are ten different triangles.
 

Ruth from Swanbourne House School gave us a little more detail about the triangles:

3 equilateral triangles where all sides are equal (3x3cm, 3x4cm and 3x5cm).
1 right angled triangle, with 1x3cm, 1x4cm and 1x5cm rod.
The other 6 were isoceles triangles, where two of the sides were equal.

Thank you to both of you.

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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.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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