**Triangles- 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. Triangles being the strongest polygon has its characteristics and properties. Unlike in earlier classes where you had learnt about congruent figures, this chapter is going to be about the similarity of geometric figures and especially of triangles. Now, let’s have a look at the mains concepts discussed in this chapter:**

- Similar polygons
- Similar triangles and their properties
- Basic results on proportionality
- Basic Proportionality Theorem
- Criteria for the similarity of triangles
- Areas of two similar triangle