# 13.3 Calculating angles_1allr

Which angle's size is
between 90° and 180°?
1 / 16
Slide 1: Open question
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This lesson contains 16 slides, with interactive quizzes and text slides.

Lesson duration is: 50 min

## Items in this lesson

Which angle's size is
between 90° and 180°?

#### Slide 1 -Open question

Types of angles
Acute angle: between 0° and 90°
Right angle: 90°
Obtuse angle: between 90° and 180°
Straight angle: 180°
Reflex angle: between 180° and 360°
Full angle: 360°
(A full angle is also called a full turn)

#### Slide 2 -Slide

Both a straight angle and a full turn look like a straight line. The arc is used to show it is an angle.

#### Slide 3 -Slide

Calculating angles

#### Slide 4 -Slide

Opposite angles
Opposite angles are the angles on opposite sides of the point of intersection of two lines. Opposite angles are always equal.

#### Slide 5 -Slide

Calculating angles
What type of angle is            ?

A4

#### Slide 6 -Slide

What type of angle is angle A4?
A
Acute angle
B
Right angle
C
Obtuse angle
D
Straight angle

#### Slide 7 -Quiz

Calculating angles
Which angle is the opposite
angle of             ?

A1

#### Slide 8 -Slide

Which angle is the opposite of angle A1?
A
A2
B
A3
C
A4
D
A5

#### Slide 9 -Quiz

Calculating angles
What size is             ?

A2

How many degrees
is angle A2?

#### Slide 11 -Open question

Calculating angles

(because they are opposite angles)

(because it is a right angle)

A3=A1=57°
A4=90°

#### Slide 12 -Slide

Calculating angles
and            are together
a ......
A1,A5
A4

#### Slide 13 -Slide

Angle A1, angle A5 and
Angle A4 are together a ....
A
full turn
B
reflex angle
C
straight angle
D
right angle

#### Slide 14 -Quiz

Calculating angles
A5=1809057=33°