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5 Shapes

!e topic of angles and lines is very important in mathematics. Key words
Understanding the basic geometry is essential in many areas,
including engineering and architecture. Make sure you learn and
understand these key words:
regular polygon
interior angle
exterior angle
isometric paper
plan
elevation

parallel
lines
Angles round a point Corresponding
Angles on a straight line
add up to 360° angles are equal
add up to 180°

parallel
lines
Alternate angles

Vertically opposite are equal
angles are equal

Angles of
a triangle Add up Exterior angle
to 180° a°
of a triangle Angles of a
quadrilateral
b° c°
Proof
a + b = c Add up to 360°

In this unit you will learn more about lines and angles in polygons, and how to make mathematical
drawings of solid shapes.

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