Egyptian Rope

We had some lovely solutions sent in for this activity, so thank you to everybody who shared their ideas with us.

Jeremy from Thailand sent us this video:

Well done for finding those three equilateral shapes. Jeremy mentions that he found another triangle that wasn't equilateral - I wonder what that one would look like?

Ci Hui Minh Ngoc from Kong Hwa School in Singapore sent in these ideas:

Well done for finding all of the possible triangles and all of the regular shapes! Ci Hui Minh Ngoc has drawn triangles whose sides are 4 x 4 x 4, 2 x 5 x 5 and 3 x 4 x 5 units of length.

Those parallelograms do have equal length sides, but they aren't classed as regular shapes. Have a close look and see if you can work out why.

William sent in this picture of his solutions:

He said:

You can basically do any shape whose sides are a factor of 12, because Egyptian Ropes have 12 knots. So a 3 sided shape like a triangle, a 4 sided shape like a rectangle or square or rhombus or parallelogram, a 6 sided shape like a hexagon, or a 12 sided shape like a dodecagon. And then have these shapes with units that add up to 12.

Good ideas, William! Can you spot which two of your shapes are actually the same?