## Types of Triangles

A triangle is a two-dimensional shape with three straight sides and three angles.

A triangle has **three sides, three vertices, and three angles**. The sum of the three interior angles of a triangle is always 180°. The sum of the length of two sides of a triangle is always greater than the length of the third side.

2D shape properties – Different Types of Triangles. A fun math video to help teach your child the 2d shape properties of triangles. Explore the different types of triangles – isosceles, equilateral, right-angled, and scalene and their properties. Learn about the different angles and properties and help your child understand the properties of each different triangle type.

Today we are going to learn about the different types of triangles.

Hi, I am Mr. Triangle. I have 3 sides and 3 angles.

Did you know that there are 3 types of triangles according to their angles and another three types of triangles according to their side’s length?

**What are the kinds of triangles according to sides?**

**s**

**calene, Isosceles, and Equilateral triangles**.

First types of triangles according to their side’s length:

1- Isosceles: I have 2 sides of equal length and one side that is different. I have 2 equal angles. You can find me in objects like:

An ice cream cone, the Eiffel Tower in France, or a slice of Pizza!

2- Equilateral: I have 3 sides of equal length and my 3 angles are the same, 60 degrees!

I can be a road sign, a pool ball rack, or a Doritos!

3- A **scale triangle** is a triangle with no sides of equal length. An isosceles triangle is a triangle with two sides of equal length. An equilateral triangle is a triangle with three sides of equal length.

**Second types of triangles according to their angles: **

1- Right-angled: One of my angles is always 90 degrees.

You can find me in sandwiches, a triangular ruler, or a ramp!

2- Acute angled triangle has three angles less than 90 degrees.

3- Obtuse angled triangle, has one angle greater than 90 degrees.

Look around you and try to find other examples!

**Real-Life Examples of Triangle**

- Bermuda Triangle. …
- Traffic Signs. …
- Pyramids. …
- Truss Bridges. …
- Sailing Boat. …
- Roof. …
- Staircase and ladder. …
- Buildings, Monuments, and Towers.

Triangles are everywhere, can you work out which type of triangle I am?

**Shapes and symmetry**

- An equilateral triangle is a triangle with all three sides of equal length. …
- An isosceles triangle is a triangle with two sides of equal length. …
- A right-angled triangle is a triangle with one angle that is a right angle.
- A scalene triangle is a triangle with all sides of different lengths.

Triangle is some of the simplest shapes there are. But this doesn’t mean that they are not important!

A triangle is a three-sided polygon and comes in a variety of flavors. Some are to do with the length of the triangle’s sides: *equilateral* — where all the sides (and all the angles) are the same size; *isosceles* — where two of the sides (and two of the angles) are the same size; and *scalene* — where none of the sides (or angles) are the same. The angles inside the triangle are also important. The sum of the angles is always 180°.

You can have *acute* triangles, where all the angles are less than 90°, and *obtuse* triangles, where one of the angles is greater than 90°. And of course, you can get *right-angled* triangles — one of the most influential mathematical shapes, inspiring Pythagoras’ Theorem and trigonometry.

But triangles aren’t just mathematically significant, they are also fundamental to the way we build our environments, both physical and virtual. Triangles are special because they are exceptionally strong. Out of all the two-dimensional shapes, we can make out of straight struts of metal, only a triangle is *rigid*.

All other shapes can be deformed with a simple push if the shape is hinged at the corners (for example, a rectangle can be pushed over into a parallelogram). But not the trusty triangle, which explains its ubiquitous use in construction, from pylons to bracing.

Triangles are also special because they are the simplest polygon — a common approach to a tricky geometrical problem, such as analyzing a complex surface, is to approximate it by a mesh of triangles. This approach is also used in the real world to achieve some exotic shapes we now see in modern architecture, such as the curved shape of 30 St Mary’s Axe, aka the Gherkin, or the canopy over the courtyard in the British Museum.

One shape is a favorite among architects, the triangle. The triangle is the strongest shape, capable of holding its shape, having a strong base, and providing immense support.

Some of the world’s most famous architectural marvels like the Eiffel Tower, the Great Pyramids of Giza, and the Louvre Pyramid use the support of triangles to make beautiful, durable structures.

Two of the most used triangles in architecture are the 30⁰, 60⁰, and 90⁰ triangle and the 45, 45, and 90⁰ triangle.

Explore the previous examples and problems, and you will find yourself getting the necessary knowledge and information to fully grasp the concept of The triangle So, keep on visiting our LearningMole.