### Adjacent Angles

#### Lesson Objective

In this lesson, we will learn about adjacent angles.

#### About This Lesson

In this lesson, we will:

- What are adjacent angles.
- See some examples on identifying them.

The study tips below will give you a short summary on this.

The math video below will explain in depth about this. Furthermore, it will show some examples so that you can understand this lesson better.

### Study Tips

#### Tip #1

There are three conditions that must be met when identifying whether two angles are adjacent angles. These conditions are:

#### Tip #2 - Special Case: Supplementary Angles

When two angles are adjacent and these angles add to 180°, these angles become supplementary angles.

#### Tip #3 - Special Case: Complementary Angles

Now, if two angles are adjacent and these angles add to 90°, these angles become complementary angles.

The math video below will explain more...

### Math Video

#### Math Video Transcript

00:00:04.090

In this lesson, we will learn about adj. angles.

00:00:09.120

Let's take a look at these two angles. 45 degrees and 110 degrees respectively.

00:00:18.020

Now, these two angles are adjacent angles.

00:00:23.180

This is because, these 2 angles shares a common side, BD, a common vertex B and these 2 angles do not overlap.

00:00:37.230

Next, when I move this arm BD, take note of the adj. angles.

00:00:52.060

Let's see some examples.

00:00:55.200

Are these adj. angles?

00:00:59.020

Let's find out. We can see that, these 2 angles have a common side AC and a common vertex A.

00:01:09.020

Furthermore, these 2 angles do not overlap. Therefore, these are adj. angles.

00:01:19.110

Next example, how about these 2 angles?

00:01:26.110

Here, we can see that, these angles have a common vertex A and common side AB. However, these angles overlap.

00:01:39.080

Hence, these are not adj angles.

00:01:44.150

Next, are these adj. angles?

00:01:50.120

Here, these 2 angles share the same vertex A.

00:01:55.070

However, these angles do not have a common side.

00:02:00.150

Hence, these are not adj. angles.

00:02:05.060

Final example, these 2 angles have a common side BC but, do not have a common vertex.

00:02:16:010

Hence, these are not adj. angles.

00:02:20.230

That is all for this lesson.

### Practice Questions & More

#### Multiple Choice Questions (MCQ)

Now, let's try some MCQ questions to understand this lesson better.

You can start by going through the series of questions on adjacent angles or pick your choice of question below.

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