8.7.4-Refine Describing Angle Relationships in Triangles

• Talk to me about linear pairs.

• What do you know about vertical angles?

• What does corresponding mean?

• What are the interior angles of a triangle?

• What are the exterior angles of a triangle?

• What does the TRIANGLE SUM THEOREM mean?

• What does SIMILAR mean? Congruent?
  

Let's Review the angle relationships we already know.

Lesson 7 OBJECTIVES:
​Reason that the sum of the measures of the interior angles of a triangle is 180 degrees.
Reason that the sum of the measures of the exterior angles of a triangle is 360 degrees.
Reason that the measures of an exterior angle of a triangle is equal to the sum of the measures of the two NON-adjacent interior angles.
Reason that two triangles are similar if two pairs of corresponding angles are congruent.
Solve problems by reasoning about angle relationships in triangles.

Multiple Choice

Are triangle ABC and triangle DEF similar?

• No

• Yes

Multiple Choice

The triangle sum theorem states that the sum of the interior angles of all triangles equals ________.

• 100*

• 180*

• 90*

• 360*

Multiple Choice

What is the measure of the missing angle?

• 43

• 63

• 137

• 53

Multiple Choice

Find the value of x by using the exterior angle theorem. (Click on the picture to make it larger and see the answers).

• A (12º)

• B (8º)

• C (15º)

• D (9º)

Multiple Choice

Calculate m∠BAD

• 76°

• 124°

• 36°

• 26°

Multiple Select

Which angle relationships are supplementary (add to 180º)? Pick 2

• Corresponding

• Alternate Interior

• Same Side Exterior

• Linear Pair

Multiple Choice

What is the measure of angle b?

• 36^o
• 56^o
• 63^o
• 117^o

Multiple Choice

What is the measure of angle x?

• 45
• 60
• 65
• 75

Multiple Choice

What is the value of x?

• 8

• 18

• 10

• 5

Multiple Choice

Which triangles are similar to triangle A?

• B
• C
• Both
• None

Multiple Choice

Sides in similar figures must be proportional.  

• True
• False 

Multiple Choice

Two objects that are the same shape but not the same size are _______.

• Congruent
• Vertical
• Similar
• Complementary 

Multiple Choice

Matching angles are called

• Corresponding Sides
• Corresponding Angles
• The Same
• Congruent Angles

Multiple Choice

Are the triangles similar?

• Yes
• No

Multiple Choice

Are the triangles similar?

• Yes
• No

Multiple Choice

All angles in similar figures are congruent.  

• True
• False

Labelling

Label the angles with the correct measures.

Drag labels to their correct position on the image

180

140

138

150

Labelling

Label the angles with the correct measures.

Drag labels to their correct position on the image

73

15

14

83

Labelling

Label the angles with the correct measures.

Drag labels to their correct position on the image

63

33

40

55

Multiple Choice

Find the measure of angle S

• A

• B

• C

• D

Multiple Choice

What is the measure of angle x?

• 45
• 60
• 65
• 75