Class 10 Mathematics — Chapter 6: Triangles
67 practice questions · 22 Easy · 23 Medium · 22 Hard
Practise Class 10 Mathematics Chapter 6, "Triangles", with 67 NCERT-aligned multiple-choice questions. The set is split into 22 Easy, 23 Medium and 22 Hard questions, so you can warm up on the fundamentals and then push into the exam-level problems that separate top scorers in CBSE Board exams and the JEE & NEET foundation years.
"Triangles" is one of the chapters where problem-solving speed, formula recall and step-by-step reasoning really pays off. Each MCQ on this chapter is timed and uses exam-grade marking (+2 correct, −1 wrong, 0 skipped), training the same accuracy-under-pressure that real papers demand. Every question carries a short explanation, so a wrong answer becomes a quick lesson rather than a dead end — the fastest way to close gaps before a test.
Use this chapter as targeted revision: attempt the Easy set first to confirm your basics on Triangles, then move to Medium and Hard to test application and problem-solving. Your accuracy, streaks and XP save automatically, and the chapter feeds into your overall Class 10 Mathematics mastery score. A few sample questions are shown below; sign in free to practise all 67.
Key concepts: Triangles (Class 10 Mathematics)
Two triangles are similar when they have the same shape but not necessarily the same size. This chapter covers the Basic Proportionality Theorem and the criteria that prove similarity.
- Similar triangles
- Corresponding angles are equal and corresponding sides are in the same ratio (denoted △ABC ~ △DEF).
- Basic Proportionality Theorem (Thales)
- A line drawn parallel to one side of a triangle divides the other two sides in the same ratio.
- Converse of BPT
- If a line divides two sides of a triangle in the same ratio, then it is parallel to the third side.
- Similarity criteria
- AAA (or AA): equal corresponding angles; SSS: sides in the same ratio; SAS: one equal angle between two proportional sides.
- Ratio of areas
- For similar triangles, the ratio of areas equals the square of the ratio of any pair of corresponding sides.
Key formulas — Triangles
💡 Exam tips for Triangles
- Name similar triangles in the correct order of corresponding vertices — it tells you which sides pair up.
- Equal angles alone (AA) are enough to prove similarity; you do not need all three sides.
Sample questions
Two triangles are similar if:
AAA: equal angles + proportional sides ⇒ similar.
In two similar triangles, ratio of areas is 16 : 25. Ratio of their corresponding sides is:
Side ratio = √(area ratio) = √(16/25) = 4/5.
ABC is a right triangle at A. If AD is the altitude to BC, with AB = 3 cm and AC = 4 cm, then AD equals:
BC = 5. Area = (1/2)(3)(4) = 6. Also = (1/2)(5)(AD) ⇒ AD = 12/5.
Triangles — FAQs
What are the key concepts in Class 10 Mathematics Triangles?+
Two triangles are similar when they have the same shape but not necessarily the same size. This chapter covers the Basic Proportionality Theorem and the criteria that prove similarity. Key ideas include Similar triangles, Basic Proportionality Theorem (Thales), Converse of BPT, Similarity criteria, Ratio of areas.
What does Class 10 Mathematics Chapter 6 (Triangles) cover on XamBaaz?+
It covers 67 NCERT-aligned MCQs on "Triangles" — 22 Easy, 23 Medium and 22 Hard — each with a timed quiz and an instant explanation, suitable for CBSE Board exams and the JEE & NEET foundation years.
Are these "Triangles" questions free to practise?+
Yes — sign in with Google to practise "Triangles" free. Full unlimited access is ₹999/year (limited-time launch price), with no per-chapter charges.
How should I revise "Triangles" for the exam?+
Start with the Easy quiz to confirm your fundamentals, then attempt Medium and Hard for application-level practice. Review each explanation, retry the questions you miss, and track your accuracy on this chapter until it is consistently high.
Practise all 67 questions free
Timed quizzes, instant scoring, streaks and XP. Sign in with Google — no card needed.
Start this chapter free →