Exterior angles of a triangle

Poll

Here’re five angles a, b, c, d and e.

Which angle(s) do you think is(are) exterior angle(s)?

• a

• b

• c

• d

• e

Draw

Draw all the exterior angles of this triangle

Draw

Can you find the unknown angle?

Draw

Can you find the unknown angle?

Draw

Can you find the unknown angle?

Draw

Can you find the unknown angle?

Draw

From the previous questions, what relation between the exterior angles and interior angles do you find in a triangle?

Draw

Can you find the unknown angle?

Multiple Choice

What is the measure of x?

• 60

• 110

• 50

• 100

Multiple Choice

Find y

• 84

• 86

• 88

• 92

Multiple Choice

Find x

• 40

• 55

• 85

• 110

Multiple Choice

Find x

• 60

• 65

• 70

• 75

Multiple Choice

Find x

• 60

• 65

• 70

• 75

Draw

Can you find the x?

Draw

Can you find the x?

Draw

Can you find the y?

Poll

What's the sum of these angles?

• 90 $$\degree$$  

• 180 $$\degree$$  

• 270 $$\degree$$  

• 360 $$\degree$$