What are ACUTE angles

We are happy to bring you again a lesson about angles, specifically about acute angles. In this lesson from a teacher you will find a simple explanation so that you understand what are acute angles with examples everyday. You will also find some more abstract and numerical examples so that you can finish understanding the lesson and put your knowledge into practice.

Index

1. What is an acute angle
2. Examples of acute angles
3. Examples of acute angles in our day to day
4. Exercise on the acute angle
5. Solution

As you may already know from other lessons from a teacher, a angleis the opening that there is between two lines joined by a vertex, which can be of different size.

In this sense, a acute angle It is in the one that has an opening less than 90º, called the acute angle. In this way, an acute angle will always be greater than 0º, but less than a right angle.

To quickly identify an acute angle, we can break a circle into four parts and the acute angle will be the one that does not reach a quarter of that circumference. Therefore, the acute angles

If you are interested in other types of angles, we recommend that you read the post Types of angles, which is more general, or other more specific ones like this one on Obtuse angles or this other about Flat angles.

Some examples of acute angles could be the following:

• 5º
• 9º
• 12º
• 16°
• 23º
• 27°
• 30º
• 35°
• 41°
• 48º
• 55º
• 58°
• The angles of an equilateral triangle, which make 60º each, as we already explained in this article.
• 61º
• 66°
• 79º
• 87º
• ...

In short, any angle not exceeding 90º, it will be an acute angle. From 0 to 90 without including either of the two, they are considered acute angles. Remember that they may not be exact, that is, they can have decimals, such as 75.25 °.

Image: Cienciamatematica.com

After seeing more abstract examples in the previous section, we are now going to see examples of more common acute angles, so that the concept is better understood. In addition, it is interesting to see the abundance of this type of angle in our day to day, since we are constantly surrounded by angles.

We go there with the examples more practical:

• The angle formed by the hands of an analog clock at five past eleven.
• Some scissors slightly open.
• A ladder leaning against a wall.
• Raise the index and middle fingers forming the victory sign.
• The letter V.
• The sharp point of a pencil.
• Our legs when we take a step.
• The lean of the Tower of Pisa in Italy.
• A clothespin.
• Each slice of a pizza cut into eight pieces.
• And many more!

I'm sure now you can easily identify acute angles. For that reason, I invite you to carry out some exercises that I leave you next.

We are going to check if you have correctly understood what an acute angle is and how to identify it through the following activities. Below you will find the solutions.

1. Mark in the following drawing three acute angles that you see.
2. Mark which of these angles are acute: 112º, 99º, 2º, 0º, 200º, 110º, 95º, 360º, 76º.
3. Look around you. On a piece of paper, write down the objects that are close to you at acute angles. You can go outside to look for elements that form this type of angle.

Let's see if you have correctly carried out the proposed activities:

1. There is no single true answer, but you have been able to find acute angles in various parts of the drawing, such as the one formed by the legs of the walking people, the one formed by the peaks of the direction signs on the left side of the image, the one that forms the brown roof of the building central...
2. Only 76º and 2º are acute angles, since the rest are obtuse angles, except 0º, which is a null angle.
3. Open answer, depending on the objects around you.

If this article has helped you to learn more about angles, I recommend that you browse the web to read other articles and thus expand your knowledge. Specifically, you can enter the section of Geometry, although you can use the search engine at the top to find what interests you the most.

If you want to read more articles similar to What are acute angles - with examples, we recommend that you enter our category of Geometry.