Thinking mathematically

There are 6 NRICH Mathematical resources connected to Thinking mathematically
The square under the hypotenuse
problem

The square under the hypotenuse

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

Can you work out the side length of a square that just touches the hypotenuse of a right angled triangle?

Polygon Rings
problem

Polygon rings

Age
11 to 14
Challenge level
filled star empty star empty star

Join pentagons together edge to edge. Will they form a ring?

Which solids can we make?
problem

Which solids can we make?

Age
11 to 14
Challenge level
filled star filled star filled star

Interior angles can help us to work out which polygons will tessellate. Can we use similar ideas to predict which polygons combine to create semi-regular solids?

Angles inside
problem

Angles inside

Age
11 to 14
Challenge level
filled star empty star empty star

Draw some angles inside a rectangle. What do you notice? Can you prove it?

Star Polygons
problem

Star polygons

Age
11 to 14
Challenge level
filled star filled star empty star

Draw some stars and measure the angles at their points. Can you find and prove a result about their sum?

Polygon Pictures
problem

Polygon pictures

Age
11 to 14
Challenge level
filled star empty star empty star

Can you work out how these polygon pictures were drawn, and use that to figure out their angles?