A triangle is made up of three points which are connected by the sides of the triangle. The sum of the angles between the points is always .

In the following, we show some special cases of triangles that have their own names.

## Right triangle

One of the angles is . The adjacent sides are called the legs and the opposite side is called the hypothenuse.

## Equilateral triangle

All sides have equal length and every angle is .

## Isosceles triangle

Two angles are equal.