Triangles are special shapes that can be grouped in different ways. We can classify them based on their sides or their angles. Each type of triangle has its own unique features, which helps us learn about geometry.

Types of Triangles by Sides:

1. Equilateral Triangle:

   • All three sides are the same length.
   • All three angles are equal, and each one measures 60 degrees.

2. Isosceles Triangle:

   • Two sides are the same length.
   • The angles opposite those sides are also the same.

3. Scalene Triangle:

   • All three sides are different lengths.
   • All angles are also different from each other.

Types of Triangles by Angles:

1. Acute Triangle:

   • All three angles are less than 90 degrees.

2. Right Triangle:

   • One angle is exactly 90 degrees.
   • The side opposite the right angle is called the hypotenuse.

3. Obtuse Triangle:

   • One angle is more than 90 degrees.
   • The other two angles are smaller and add up to less than 90 degrees.

Knowing about these different kinds of triangles is super helpful. It makes solving geometry problems easier and helps us understand important math concepts. Each triangle type teaches us something different, which is really useful for doing well in Grade 11 math.