In this lesson, we will learn about obtuse triangles...
About This Lesson
In this lesson, we will:
- learn what are obtuse triangles.
- 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.
When one of the internal angle of a triangle is greater than 90°, this triangle can be called an obtuse triangle. See some examples below:
The math video below will explain more...
Math Video Transcript
In this lesson, we will learn about obt. triangles (OT).
A triangle is an OT, when it has an internal angle that is greater than 90 degrees.
Now, to demonstrate this, let's move vertex 'A' to the left
Notice that, when the angle at vertex 'B' is greater than 90 degrees, this triangle becomes an OT.
Next, let's move this vertex, to the right..
Here, we get another OT, when the angle at vertex 'C', is greater than 90 degrees.
Let's move vertex 'A'…and vertex 'C'.
Again, we get another OT, when the angle at vertex 'A' is greater than 90 degrees.
Let's see some examples.
Is this an OT?
Notice that, this angle is greater than 90 degrees.
Therefore, this is an OT.
Next example, how about this triangle?
In this triangle, there are no angles that are greater than 90 degrees.
Hence, this is not an OT.
That is all for this lesson.
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