# Lesson Video: Triangles Mathematics • Kindergarten

In this video, we will learn how to identify triangles regardless of their orientation, size, or color.

04:27

### Video Transcript

Triangles

In this video, we will learn how to identify triangles regardless of their orientation, size, or color. A triangle is a 2D shape. Triangles have one, two, three sides. Each of the sides is straight. So we can say that triangles have three straight sides. Triangles also have three corners or vertices. Triangles can come in different colors and different sizes. They can also come in different orientations. That means we can turn a triangle around. It’s still a triangle. We know a 2D shape is a triangle if it has three sides and three corners.

Let’s practice identifying triangles using these features with some practice questions.

Which of these is a triangle?

In this question, we’re shown three different 2D shapes. We have to choose the one which is a triangle. Triangles have three straight sides and three corners. Which of these shapes has three sides and three corners? Let’s count the number of sides that the first shape has. One, two, three, four. This shape has four sides. It’s not a triangle. Let’s count the number of sides that the second shape has. One, two, three. Let’s check it has three corners. One, two, three. Yes it does. This shape is a triangle.

Pick the matching shape.

We’re shown a shape. It’s an orange shape. It has three straight sides and three corners. This shape is a triangle. Which of these shapes is also a triangle? Both of these shapes have four sides, so they’re not triangles. Triangles have three sides. Is this a triangle? It does have three sides and three corners. It’s a triangle. This is the matching shape. They’re both triangles.

Choose the triangle.

We’re shown five different 2D shapes. We have to choose the one which is a triangle. Triangles have three straight sides and three corners. This is a circle, doesn’t have any corners or any straight sides. This shape has four straight sides, so it can’t be a triangle. These two shapes also have four straight sides. So we know they’re not triangles either. This shape has three straight sides and three corners. It’s a triangle. We chose the triangle.

What have we learned in this video? We’ve learned how to identify triangles. We’ve also learned that triangles have three straight sides and three corners.