# Identifying Relationships between Angles

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Slide 1: Interactive video with 14 slides
math

This lesson contains 15 slides, with interactive quizzes, text slides and 1 video.

## Items in this lesson

#### Slide 1 -Video

00:41
Prior Knowledge Check
What are lines that extend forever, and never cross, called?

#### Slide 2 -Mind map

01:17
Remember!
The point at which lines cross is called an
intersection.

#### Slide 3 -Slide

01:46
Remember!
The name of an angle is based on the labels of each point!

For example, this is angle ABC because each "point" has a label of either A, B, or C!

#### Slide 4 -Slide

03:13
Ah-ha!
Arcs also name angles!
For example,
Angle ABC can also be Arc ABC!

#### Slide 5 -Slide

03:40
Perpendicular Lines
Lines that cross and form "perfect T's" or "perfect squares" are called perpendicular lines!
***With perpendicular lines, ALL ANGLES ARE EQUAL!***

#### Slide 6 -Slide

03:57
Ah-ha!
ALL right angles have a tiny square in their corner, which is formed by perpendicular lines.  If it does not have a square in the corner, more than likely, it's not a right angle!

#### Slide 7 -Slide

04:46
Review
Right angle - Forms a perfect "L" and has a square inside its angle; equal to 90 degrees
Acute angles - smaller than a right angle; less than 90 degrees
Obtuse angles - bigger than a right angle; more than 90 degrees

#### Slide 8 -Slide

05:13
What kind of angle is this?
A
obtuse
B
straight
C
right
D
acute

#### Slide 9 -Quiz

05:13
What kind of angle is this?
A
acute
B
obtuse
C
right
D
straight

#### Slide 10 -Quiz

05:13
What kind of angle is this?
A
acute
B
obtuse
C
straight
D
right

#### Slide 11 -Quiz

05:40
Complementary Angles
Complementary angles are angles that are formed by 2 angles that, when you add the measurement of both of their angles and combine them, form a right angle.
**The two angles together equals 90 degrees!***

#### Slide 12 -Slide

05:57
Supplementary Angles
Supplementary angles are formed when two angles, whose individual angles are combined, add up to a straight angle.
***The two angles together equal 180 degrees!***

#### Slide 13 -Slide

06:19
Lines that point in the same direction and never touch are called...
A
perpendicular
B
right
C
straight
D
parallel

#### Slide 14 -Quiz

07:42
Time to Practice!