Equilateral Triangle

Lesson Objective

In this lesson, we will learn about equilateral triangles...

Study Tips

Tip #1

When a triangle has three sides (edges) of equal length, this triangle can be called an equilateral triangle. See some examples below:

Tip #2

Since this type of triangle has three sides of equal length, each of its internal angles is 60°. See the picture below:

The math video below will explain more...

Math Video

Lesson Video

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Math Video Transcript

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In this lesson, we will learn about equi. triangle.

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A triangle is an equi. triangle, when all the sides of the triangle, have the same length.

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Now, to demonstrate this, let's move vertex 'B' to the right.

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Here, we can see that when all the 3 sides have the same length, we get an equi. triangle.

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Also, it is important to note that, each of its internal angles is equal to 60 degrees.

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Let's see some examples.

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Is this an equi. triangle?

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Since this triangle has 3 sides of equal length, this is an equi. triangle.

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Next example, how about this triangle?

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We can see that, all these angles are 60 degrees.

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This means that, these 3 sides must have the same length.

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Hence, this is an equi. triangle.

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Last example, now, only these 2 sides have the same length.

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Therefore, this is not an equi. triangle.

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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 equilateral triangles or pick your choice of question below.

Question 1

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