Pythagoras' theorem

There are 108 NRICH Mathematical resources connected to Pythagoras' theorem
Pythagoras Proofs
problem
Favourite

Pythagoras proofs

Age
11 to 16
Challenge level
filled star filled star empty star

Can you make sense of these three proofs of Pythagoras' Theorem?

Garden Shed
problem
Favourite

Garden shed

Age
11 to 14
Challenge level
filled star filled star empty star
Can you minimise the amount of wood needed to build the roof of my garden shed?
Kite in a Square
problem
Favourite

Kite in a square

Age
14 to 18
Challenge level
filled star filled star empty star
Can you make sense of the three methods to work out what fraction of the total area is shaded?
Generating Triples
problem
Favourite

Generating triples

Age
14 to 16
Challenge level
filled star empty star empty star
Sets of integers like 3, 4, 5 are called Pythagorean Triples, because they could be the lengths of the sides of a right-angled triangle. Can you find any more?
Zig Zag
problem
Favourite

Zig zag

Age
14 to 16
Challenge level
filled star filled star empty star
Four identical right angled triangles are drawn on the sides of a square. Two face out, two face in. Why do the four vertices marked with dots lie on one line?
Orthogonal Circle
problem
Favourite

Orthogonal circle

Age
16 to 18
Challenge level
filled star filled star empty star
Given any three non intersecting circles in the plane find another circle or straight line which cuts all three circles orthogonally.
Partly Circles
problem
Favourite

Partly circles

Age
14 to 16
Challenge level
filled star filled star filled star
What is the same and what is different about these circle questions? What connections can you make?
Three cubes
problem
Favourite

Three cubes

Age
14 to 16
Challenge level
filled star filled star empty star
Can you work out the dimensions of the three cubes?
Hex
problem
Favourite

Hex

Age
11 to 14
Challenge level
filled star empty star empty star
Explain how the thirteen pieces making up the regular hexagon shown in the diagram can be re-assembled to form three smaller regular hexagons congruent to each other.
Pythagoras for a Tetrahedron
problem
Favourite

Pythagoras for a tetrahedron

Age
16 to 18
Challenge level
filled star filled star filled star

In a right-angled tetrahedron prove that the sum of the squares of the areas of the 3 faces in mutually perpendicular planes equals the square of the area of the sloping face. A generalisation of Pythagoras' Theorem.