Scalene, Isosceles, and Equilateral Triangles

Do you remember how to identify triangles by their angles? 🤔

We can also identify triangles by comparing the lengths of sides **and** angles.

Let's learn some more triangle types! 🤗

**Scalene triangles** have no equal sides and no equal angles.

Do you see how all three sides have a different length?

AND all three angles are different?

Great! Let's look at another! 👇

**Isosceles triangles** have two equal sides and two equal angles.

We have two 70-degree angles AND two sides that have a length of 8.

Last one! 👇

**Equilateral triangles** have three equal sides and three equal angles.

👉** Hint**: The equal angles always measure 60°.

**Tip:** The 3 angles in all triangles sum up to 180°.

So if you can't remember the angles in an equilateral triangle, just divide 180° by 3!

Now let’s try to identify triangles as scalene, isosceles, or equilateral.

What kind of triangle is this? 👇

That’s it!

✅ This is an** isosceles triangle**. It has 2 equal sides and 2 equal angles.

Let’s try another one. 🤔

What kind of triangle is this?

Good job!

✅ This is a **scalene triangle**. None of the sides or angles are equal. Each side and angle has a different measurement.

Let's try one more!

What kind of triangle is this?

That’s right!

✅ This is an **equilateral triangle. ** We can see that the triangle has 3 equal sides and 3 equal angles that all measure 60°.

Great job! 🤗 Now, you can identify scalene, isosceles, or equilateral triangles!

It's time to move on to practice! 😃

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