Triangles

There are 116 NRICH Mathematical resources connected to Triangles
Four Triangles Puzzle
problem

Four Triangles Puzzle

Age
5 to 11
Challenge level
filled star empty star empty star
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?
Tessellating Triangles
problem

Tessellating Triangles

Age
7 to 11
Challenge level
filled star empty star empty star
Can you make these equilateral triangles fit together to cover the paper without any gaps between them? Can you tessellate isosceles triangles?
Let's Investigate Triangles
problem

Let's Investigate Triangles

Age
5 to 7
Challenge level
filled star empty star empty star
Vincent and Tara are making triangles with the class construction set. They have a pile of strips of different lengths. How many different triangles can they make?
Bracelets
problem

Bracelets

Age
7 to 11
Challenge level
filled star empty star empty star
Investigate the different shaped bracelets you could make from 18 different spherical beads. How do they compare if you use 24 beads?
Cutting Corners
problem

Cutting Corners

Age
7 to 11
Challenge level
filled star empty star empty star
Can you make the most extraordinary, the most amazing, the most unusual patterns/designs from these triangles which are made in a special way?
Tri.'s
problem

Tri.'s

Age
7 to 11
Challenge level
filled star empty star empty star
How many triangles can you make on the 3 by 3 pegboard?
Liethagoras' Theorem
article

Liethagoras' Theorem

Liethagoras, Pythagoras' cousin (!), was jealous of Pythagoras and came up with his own theorem. Read this article to find out why other mathematicians laughed at him.