Chapter 7 of 12
Syllabus
Triangles — Syllabus
Tripura Board · Class 9 · Mathematics
What Triangles covers in Tripura Board Class 9 Mathematics: 4 topics, for the 2026-27 session. Part of the Tripura Board Class 9 Mathematics syllabus.
41 questions22 flashcards5 concepts
Interactive on Super Tutor
Studying Triangles? Get the full interactive chapter.
Quizzes, flashcards, AI doubt-solver and a step-by-step study plan — built for syllabus and more.
Free trial, no card needed.

Super Tutor
Learn better with visuals Super Tutor pairs illustrations like this with notes and quizzes for Triangles.
4 Topics · Tripura Board Class 9 Mathematics · 2026-27
Topics in Triangles
1
Congruence of Triangles
- Two figures are congruent if they have the same shape and size
- Congruent triangles can be placed on each other to cover completely
- When ΔABC ≅ ΔPQR, corresponding parts are equal (CPCT)
2
Criteria for Congruence of Triangles
- One side or one angle equality is not sufficient for congruence
- SAS (Side-Angle-Side): Two sides and included angle must be equal
- ASA (Angle-Side-Angle): Two angles and included side must be equal
3
Properties of Isosceles Triangles
- Isosceles triangle has two equal sides
- Angles opposite to equal sides are equal (base angles)
- Converse: If two angles are equal, opposite sides are equal
4
Proof Techniques and Applications
- ASA theorem proof uses SAS axiom
- Construction method for proving SSS congruence
- Indirect proof method (assuming opposite)
Key Concepts
Two figures are congruent if theyTwo triangles are congruent if twoTwo triangles are congruent if twoTwo triangles are congruent if anyTwo triangles are congruent if all
Work through every topic in Triangles with notes and quizzes
Start This ChapterFrequently Asked Questions
What are the important topics in Triangles for Tripura Board Class 9 Mathematics?
Key topics in Triangles include Congruence of Triangles, Criteria for Congruence of Triangles, Properties of Isosceles Triangles, Proof Techniques and Applications. Study these first, then practise questions on each for Class 9 exams.
How should I revise Triangles for Class 9 exams?
Learn the core ideas first, then work through the 41 practice questions on Triangles. Revise definitions regularly and use flashcards for quick recall before the exam.
Sources & Official References
Content is aligned to the official syllabus. Refer to the board website for the latest curriculum.
More resources for Triangles
For serious students
Get the full Triangles chapter — start free.
Quizzes, flashcards, an AI doubt solver and a study plan for Tripura Board Class 9 Mathematics. Free to start, no card needed.