Angle Types and Pairs

How much do you feel you know about angle pairs?

• This stuff is great and I understand the definitions

• I remember hearing this before, but need some more review.

• I don't remember hearing about this before, but think I understand.

• I am totally lost!

Tags

CCSS.7.G.B.5

_{What is the measure of the following angle?}

• 100 degrees.

• 58 degrees. 
• 78 degrees

• 102 degrees

Answer explanation

Notice how the degrees are labeled on an arc on the protractor. There are two sets of degrees going in opposite directions along an arc. The bottom of the arc shows degrees from 0º to 180º from left to right. The top of the arc shows degrees from 180º to 0º from left to right.

This is an obtuse angle, so the answer is GREATER than 90 degrees.

Tags

CCSS.4.MD.C.6

This is what kind of angle?

• obtuse
• right
• straight
• acute

Answer explanation

An acute angle is one that measures less than 90 degrees.

It is sometimes called a "sharp" angle

The word acute comes from Latin, acutus, meaning sharp or pointed. Anytime you see a pointy angle, you have an acute angle.

Tags

CCSS.4.G.A.1

This type of angle shares a common side and a common vertex.

• Vertical Angles

• Obtuse Angles

• Adjacent Angles

• Acute Angles

Answer explanation

Adjacent angles can be complementary, supplementary or neither. The thing is , they must share a common side and a common vertex.

Tags

CCSS.7.G.B.5

What term is used to describe a pair, or group, of angles that equal 180 degrees?

• Supplementary Angles
• Complementary Angles
• Vertical Angles
• Congruent Angles

Answer explanation

Supplementary angles refer to the pair of angles that always sum up to 180°. These two angles are called supplements of each other. The word "supplementary" comes from two Latin words "Supplere" and "Plere" where "Supplere" means "supply”, whereas "Plere" means "fill". So, "supplementary" means "something when supplied to complete a thing".

Tags

CCSS.7.G.B.5

Solve for x.

• x = 118
• x = 108
• x = 28
• x = 58

Answer explanation

x + 62 = 180

x +62 - 62 = 180 - 62

x = 118

Check:

118 + 62 = 180

180 = 180

Tags

CCSS.7.G.B.5

What are vertical angles?

• Angles that are adjacent to each other
• Angles that add up to 180°
• Angles that are opposite of each other when lines intersect
• Angles that add up to 90°

Answer explanation

Real-life settings where vertical angles are used include railroad crossing sign, letter “X’’, open scissors etc.

The Egyptians used to draw two intersecting lines and always measure the vertical angles to confirm that both of them are equal.

Tags

CCSS.7.G.B.5

What is an example of a pair of complementary angles?

• 13° and 45°
• 10° and 170°
• 81° and 9°
• 90° and 3°

Answer explanation

Complementary comes from Latin completum meaning "completed" ...because the right angle is thought of as being a complete angle.

Spelling: be careful, it is not "Complimentary Angle" (with an "i") ...that would be an angle you get for free!

Tags

CCSS.7.G.B.5

Are these angles complementary, supplementary or neither?

• complementary
• supplementary
• neither

Answer explanation

Two Angles that have a sum of 90 degrees are complementary.

Tags

CCSS.7.G.B.5

Choose all answers that apply: Find the angle measurements that are complementary to each other.

• 75 and 105

• 75 and 15

• 25 and 65

• 34 and 146

• 38 and 52

Answer explanation

Fun Facts!

*The two angles don't always have to be put together to be complementary.

*A complementary angle is made up of two acute angles.

Tags

CCSS.7.G.B.5