### The sides of a triangle

**Every triangle has three sides**. That also works the other way around - if we see a shape with tree sides, it's a triangle.

##### types of triangles based on the sides:

The sides allow us to classify the different types of triangles according to their size:

**Equilateral**: All sides are equal, leading to equal angles.**Isosceles**: Two sides are equal, with base angles also equal.**Scalene**: All sides are different lengths, with all angles unique.

##### Perimeter of a Triangle

Like every polygon, the sides of a triangle form its perimeter. To find the perimeter of a triangle, simply add the lengths of all three sides.

##### Relation between the sides and the angles in a triangle

In a triangle, there’s a direct relationship between the length of a side and the size of the angle across from it:

The **Longer Side** will always be in the opposite side of the **larger Angle**, and the **shorter side** will always be in the opposite side of the **smaller Angle**.

##### Can every three lines form a triangle?

In any triangle, the sum of the two shorter sides must always be greater than the length of the third side. This rule, known as the **Triangle Inequality Theorem**, ensures that the sides can actually form a closed triangle. For example, if the two shorter sides are not greater than the third, the sides would lie flat rather than forming a triangle. This principle is crucial in determining whether a set of side lengths can create a valid triangle.