Class 10 Maths Chapter 6 – Triangles | Similarity, Theorems, NCERT Solutions & CBSE Questions (2025–26)
Class 10 CBSE Maths – Chapter 6:Triangles 🔹 Key Concepts and Theorems ✅ Similar Figures Figures having the same shape but not necessarily the same size. All congruent figures are similar but not all similar figures are congruent. ✅ Similar Triangles Two triangles are similar if: Their corresponding angles are equal Their corresponding sides are in the same ratio (proportional) Criteria for Similarity of Triangles: AA (Angle-Angle) Criterion : Two triangles are similar if two angles of one triangle are respectively equal to two angles of another triangle. SSS (Side-Side-Side) Criterion : If the sides of two triangles are in the same ratio, then the triangles are similar. SAS (Side-Angle-Side) Criterion : If one angle of a triangle is equal to one angle of another triangle and the sides including these angles are in the same ratio. ✅ Basic Proportionality Theorem (Thales Theorem) Statement: If a line is drawn parallel to one side of a triang...