© Nuffield Foundation 2011

Nuffield Free-Standing Mathematics Activity

Geometrical design

Geometrical design

Can you name any of the geometrical shapes in these pictures?

This activity is about recognising shapes and their properties

Left-hand photo Decoramic Tile Centre http://www.decoramic.co.uk/

perpendicular lines

are always the same distance apart

Think aboutWhat is special about….

parallel lines

meet at 90

has one angle of 90

a right-angled triangle

an obtuse-angled triangle

has one angle greater than 90

an acute-angled triangle

has three angles all less than 90

Think aboutWhat is special about ….

Triangles

Think aboutWhy is it not possible for a triangle to have more than one right angle?

have 3 sides and 3 anglessum of the angles = 180

has3 equal sides and 3 equal angles. has

2 equal sides and 2 equal angles.

an equilateral triangle

an isosceles triangle

a scalene triangle

has3 different sides and 3 different angles.

Think aboutWhat is special about….

Triangles

Think aboutWhat is each angle in an equilateral triangle?

A quadrilateral has 4 sides.

A pentagon has 5 sides.

A hexagon has 6 sides.

An octagon has 8 sides

Think aboutthe names of these polygons….Polygons

Sum of the angles = 360

Rectangle Square

Opposite sides equal All sides equal

Think about …What is special about these quadrilaterals?

Opposite sides parallel Opposite sides parallel

Quadrilaterals

All angles are 90⁰ All angles are 90⁰

Opposite angles equal Opposite angles equal

Parallelogram

Opposite sides parallel Opposite sides parallel

RhombusAll sides equalOpposite sides equal

Think about …What is special about these quadrilaterals?

Quadrilaterals

Kite

Two pairs of equal sides

Trapezium

One pair of sides parallel

Think aboutWhat is special about these quadrilaterals?

Quadrilaterals

One pair of equal angles

Think about …What does ‘regular’ mean?

Regular polygons

Think aboutWhat is another name for a regular triangle?What is another name for a regular quadrilateral?

Key wordsregular parallel perpendicularcircle

trianglesscalene isosceles equilateralacute-angled right-angled obtuse-angledquadrilateralsparallelogram trapezium rhombusrectangle square kiteother polygonspentagon hexagon octagon

Geometrical designAt the end of the activity

Name the different types of triangles.

Name each special type of quadrilateral. List their properties.

What does the term 'regular' mean? What is another name for a regular quadrilateral?

What types of jobs involve using geometrical shapes? List as many as you can.