Triangle Sum/Exterior Angle Theorem

Triangle Sum/Exterior Angle Theorem

Why do triangles always equal 180^o?

https://www.youtube.com/watch?v=hEAFyu_tA7g

Fill in the Blank

How many degrees are in ALL triangles?

Multiple Choice

What is the measure of the missing angle?

• 82
• 43
• 55
• 180

Multiple Choice

Find the measure of the missing angle.

• 47

• 57

• 53

• 133

Multiple Choice

What is the measure of a third angle in a triangle when the first two angles measure

 $34\degree\ and\ 101\degree$  ?

•  $32\degree$  

•  $45\degree$  

•  $54\degree$  

•  $39\degree$  

Multiple Choice

Solve for x.

• 5

• 12

• -7

• -6

Multiple Choice

Solve for x.

• -12

• -8

• -10

• -5

Multiple Choice

Solve for x.

• 16

• 11

• 50

• 6

Multiple Choice

Solve for x

• 28
• 12
• 10
• 2

Exterior Angle Theorem Activity

Multiple Choice

Find the measure of each angle indicated.

• $50\degree$

• $120\degree$

• $30\degree$

• $20\degree$

Multiple Choice

What is the measure of x?

• 101°

• 111°

• 121°

• 131°

Multiple Choice

Find the indicated angle measure. 

(What is ?)

• $5\degree$

• $165\degree$

• $65\degree$

• $60\degree$

Multiple Choice

Find the indicated angle measure.

(What is ?)

• 85

• 78

• 95

• 110

Multiple Choice

Solve for x

• 3

• 4

• 2

• 1

Multiple Choice

Solve for x

• 48

• 85

• 24

• 9

Multiple Choice

Set up an equation to find x.

• 42 + 8x = 2 + 12x

• 2 + 12x + 42 = 8x

• 42 + 8x + 2 + 12x = 180

• 42 + 8x = 180

Multiple Choice

Which of the following angles are remote interior angles to

 $\angle d$  ?

•  $\angle a\ and\ \angle b$  

•  $\angle a\ and\ \angle c$  

•  $\angle b\ and\ \angle d$  

•  $\angle a,\ \angle b,\ and\ \angle c$