Triangles

There are 117 NRICH Mathematical resources connected to Triangles

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Favourite

Isosceles seven

Age

14 to 16

Challenge level

Is it possible to find the angles in this rather special isosceles triangle?

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Favourite

Triangle or no triangle?

Age

5 to 7

Challenge level

Here is a selection of different shapes. Can you work out which ones are triangles, and why?

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Favourite

Name that triangle!

Age

7 to 11

Challenge level

Can you sketch triangles that fit in the cells in this grid? Which ones are impossible? How do you know?

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Favourite

Constructing triangles

Age

11 to 14

Challenge level

Generate three random numbers to determine the side lengths of a triangle. What triangles can you draw?

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Favourite

Walking round a triangle

Age

5 to 7

Challenge level

This ladybird is taking a walk round a triangle. Can you see how much he has turned when he gets back to where he started?

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Favourite

Data shapes

Age

5 to 7

Challenge level

Sara and Will were sorting some pictures of shapes on cards. "I'll collect the circles," said Sara. "I'll take the red ones," answered Will. Can you see any cards they would both want?

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Favourite

Four triangles puzzle

Age

5 to 11

Challenge level

Cut four triangles from a square as shown in the picture. How many different shapes can you make by fitting the four triangles back together?

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Favourite

Triangle animals

Age

5 to 7

Challenge level

How many different ways can you find to join three equilateral triangles together? Can you convince us that you have found them all?

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Favourite

Repeating patterns

Age

5 to 7

Challenge level

Try continuing these patterns made from triangles. Can you create your own repeating pattern?

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Favourite

Transformations on a pegboard

Age

7 to 11

Challenge level

How would you move the bands on the pegboard to alter these shapes?

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For younger learners

Triangles

Isosceles seven

Triangle or no triangle?

Name that triangle!

Constructing triangles

Walking round a triangle

Data shapes

Four triangles puzzle

Triangle animals

Repeating patterns

Transformations on a pegboard