Geometry 5

Level 1

Interior angles in a triangle

Interior angles in a quadrilateral

Interior angles in a pentagon

Interior angles in a pentagon

Interior angles in a hexagon

General rule

Sum of interior angles = (number of sides - 2) x 180

Exterior angles = 360 degrees

Equilateral triangle

Equilateral triangle. All angles are the same.

Exterior angles = 360 degrees

120

120

120

60

60

60

Angles on a line sum to 180

120

120

120

60

60

60

A square is a regular quadrilateral

90

90

90

90

Interior angles are all 90

90

90

90

90

Exterior angles are all 90 and add up to 360

90

90

90

90

Regular pentagon

Exterior angles add up to 360

Exterior angles add up to 360

Exterior angles add up to 360

Interior angles are on a line with exterior angles

Interior angles are on a line with exterior angles

Find the interior and exterior angles of a regular hexagon.

Exterior angles.

Interior angles.

How many sides does a regular polygon have if the

exterior angles are 45 degrees?

How many sides does a regular polygon have if the

exterior angles are 45 degrees?

How many sides does a regular polygon have if the

interior angles are 144 degrees?

How many sides does a regular polygon have if the

interior angles are 144 degrees?

Exterior angle

Number of sides

Find all the angles