12/9 Lesson Angles and Measures

Angle Pairs and Measurements

Angles are measured in degrees

How to label an angle in a diagram

Match

Match the angle pair with its property

• Vertical Angles are:

• Supplementary angles have:

• Complementary angles have:

congruent (equal)

a sum of 180

a sum of 90

• congruent (equal)

• a sum of 180

• a sum of 90

Please take out your notes: MP -I2 - unknown angles

On the next 3 slides we will go over Example 1

You will need to find both the measure and
the type of angle pair.

Drag and Drop

The value of ∠a =​

Placeholder

because it is ​

Placeholder

to 40 and supplementary angles have a sum of ​

Placeholder

.

Drag these tiles and drop them in the correct blank above

140

supplementary

40

vertical

50

complementary

180

90

Drag and Drop

The value of ∠b =​

Placeholder

because it is ​

Placeholder

to 40 and vertical angles are ​ ​

Placeholder

.

Drag these tiles and drop them in the correct blank above

140

supplementary

40

vertical

50

complementary

equal

Drag and Drop

The value of ∠c =​

Placeholder

because it is ​

Placeholder

to 40 and complementary angles have a sum of ​ ​

Placeholder

.

Drag these tiles and drop them in the correct blank above

140

supplementary

40

vertical

50

complementary

90

180

​Please take out your notes: MP -I2 - unknown angles

The next 3 slides will go over how to do Example 2

This example uses the property of vertical angles and supplementary angles.

Multiple Choice

What is the measure of $$\angle a$$

• 110

• 70

Multiple Choice

What is the measure of $$\angle b$$

• 110

• 70

Multiple Choice

What is the measure of $$\angle c$$

• 110

• 70

​Please take out your notes: MP -I2 - unknown angles

The next 3 slides will go over how to do Example 3

Drag and Drop

The value of ∠a =​

Placeholder

because vertical angles are ​

Placeholder

Drag these tiles and drop them in the correct blank above

20

equal

60

Drag and Drop

The value of ∠b =​

Placeholder

because vertical angles are ​

Placeholder

Drag these tiles and drop them in the correct blank above

20

equal

60

Drag and Drop

The equation to find the value of x is ​

Placeholder

because they are in a straight lines which has an angle of ​

Placeholder

Drag these tiles and drop them in the correct blank above

90

5x+10+60+20 = 180

5x+10=90

5x+10=80

80

​To find the value of x:

​1) combine like terms
2) get all constants to right side
3) divide by the coefficient

You can fill in the notes to remember

The next slides will be some practice questions

Multiple Choice

Find the missing angle.

• 43

• 47

• 57

• 67

Multiple Choice

What is the measure of the missing angle?

• 92
• 102
• 82
• 72

Multiple Choice

Find the missing angle.  Find x.

• 20^o
• 70^o
• 160^o
• 180^o

Multiple Choice

What is the supplement angle to 42°?

• 48°
• 138°
• 100°
• Not possible

Multiple Choice

What is the complement angle to 30°?

• 60°
• 30°
• 150°
• 230˚

Poll

How well do you understand the angle pairs?

• I understand

• I am getting it

• I need more practice

• I have no clue