# Angles (Elementary)

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 Mentor: Today we are going to learn about angles. Student: I know what an angle is! It is two rays connected together. Mentor: Good job! Did you read that from your book? Student: Yes. Mentor: Well, there are three categories of angles: acute, obtuse and right. Let's learn what a right angle is first. Right angles are present many places in real life. Look at the corners of this room or the edges of your books. A right angle is an angle that measures 90 degrees. A right angle looks like this: Mentor: The second type of angle is acute. An acute angle is an angle whose measure is between 0 and 90 degrees. An acute angle looks like this: Student: Let me guess! The third type is an angle whose measure is more than 90 degrees. Mentor: Yes, an obtuse angle is an angle whose measure is between 90 and 180 degrees. An obtuse angle looks like this: Mentor: We also usually name angles. Look at how these lines intersect and form angles. Student: Those lines formed 8 angles. Mentor: Good job. Now, who can show me an acute angle? Student: I can! It is the one on the top right. Mentor: Right again. Who can show me an obtuse angle? Student 2: I think it is the one on the top left. Mentor: Correct. We need an easier way of referring to the angles we are talking about. So from now on, we will label our angles. Mentor: Who knows the names of the angles in this picture that are acute? Student: Do you just call them by the letter that we put there? Mentor: Yes, that's exactly what you do. Now what are the names of the angles that are acute? Student: Angles b, c, f, and g. Mentor: Good job, now you know the different types of angles and how we name angles. I think you're ready to put those ideas into practice!