A triangle that has three acute angels is called an acute triangle. A triangle that has one right angle is called a right triangle. A triangle that has one obtuse angle is called an obtuse triangle. When a triangle has three congruent sides, we call the triangle an equilateral triangle.
Isosceles Triangle: An isosceles triangle is a triangle that has two sides with the same length, and therefore two angles with the same value.
According to internal angles, there are three types of triangles i.e., acute, right, and obtuse-angled triangle. According to the length of sides, triangles can be classified into 3 categories i.e., Scalene, Isosceles, and Equilateral triangle.