### Straight Angle

#### Lesson Objective

In this lesson, we will learn about straight angle.

#### About This Lesson

After knowing what are obtuse angles, we will now learn:

- What is a straight angle.
- See some examples on identifying it.

The study tips below will give you a short summary and it can be used to recall the properties of this angle.

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

### Study Tips

#### Tip #1

If an angle is exactly 180°, it is a straight angle. The picture below shows some examples:

### Math Video

#### Lesson Video

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Straight Angles from MathExpression.com on Vimeo.

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I'd like to contribute or to know more about the app#### Math Video Transcript

00:00:03.200

In this lesson, we will learn about this type of angle.

00:00:08.120

Let's take a look at this angle.

00:00:11.200

In the previous lesson, we learned that an obtuse angle is always more than 90 degrees, and less than 180 degrees.

00:00:20.210

What happens, when the angle becomes 180 degrees?

00:00:26.140

When the angle becomes 180 degrees, it is called a str. angle.

00:00:32.230

To emphasize, str. angle is an angle that is equals to 180 degrees.

00:00:40.090

Let's see some examples.

00:00:43.130

Is this a str. angle?

00:00:48.030

Yes! It is.

00:00:51.210

How about this angle?

00:00:55.140

Again, this is a str. angle.

00:00:59.240

Next example, is this a str. angle?

00:01:05.030

Clearly, this angle is not equals to 180 degrees.

00:01:10.160

Hence, this is not a str. angle

00:01:15.220

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 straight angle or pick your choice of question below.

- Question 1 on identifying this type of angle.

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