RS Aggarwal Solutions for Class 6 Chapter 16, “Triangles” and its Classification of Triangle. A triangle is a polygon with three edges and three vertices. It is one of the basic shapes in geometry. A triangle with vertices A, B, and C is denoted. In Euclidean geometry, any three points, when non-collinear, determine a unique triangle and simultaneously, a unique plane. Types of triangles are Congruent triangles, interior and exterior of a triangle, various kinds of triangles namely equilateral triangle, isosceles triangle, scalene triangle, the perimeter of a triangle, naming triangles by considering their angles such as acute triangle, right triangle and obtuse triangle and angle sum property of a triangle. Traffic signs, roof, staircase and ladder, buildings, monuments, towers etc. are examples of triangles used in daily life.