What are the coordinates of the coloured dots that mark out the tangram? Try changing the position of the origin. What happens to the coordinates now?

Find the missing coordinates which will form these eight quadrilaterals. These coordinates themselves will then form a shape with rotational and line symmetry.

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

These points all mark the vertices (corners) of ten hidden squares. Can you find the 10 hidden squares?

Use the interactivity to find all the different right-angled triangles you can make by just moving one corner of the starting triangle.

Use the clues about the symmetrical properties of these letters to place them on the grid.

On the graph there are 28 marked points. These points all mark the vertices (corners) of eight hidden squares. Can you find the eight hidden squares?

Can you find a reliable strategy for choosing coordinates that will locate the treasure in the minimum number of guesses?