Skip to main content
Super TutorResources
Chapter 9 of 28
QuestionsNotesFlashcardsSummaryFormulasQuizConceptsSyllabusPlan
Practice Quiz

Triangles

ICSE · Class 9 · Mathematics

Practice quiz for Triangles — ICSE Class 9 Mathematics. MCQs and questions with answers to test your preparation.

40 questions30 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 practice quiz and more.

Try Super Tutor — Free

1,000+ Class 9 students started this chapter today

A labeled diagram showing the vertices, sides, and angles of a basic triangle ABC.
Super Tutor

Learn better with visuals Super Tutor has hundreds of illustrations like this across every chapter — all free to try.

Get started

Quick Quiz: Triangles

0/4

Tap an answer to check it instantly. No sign-up needed for these 4.

1

Two triangles ABC and DEF have AB = DE = 6 cm, BC = EF = 4 cm, and ∠B = ∠E = 60°. By which congruence criterion are they congruent?

2

In a triangle, the sum of any two sides must be:

3

If in triangle PQR, ∠P = 70° and ∠Q = 50°, find ∠R:

4

In an isosceles triangle ABC with AB = AC, if ∠A = 40°, find ∠B:

40 Questions·
multiple choicemultiple correct

Sample Questions

1multiple correct

Which of the following are valid congruence criteria for triangles? (Select all that apply)

Show answer

SSS, SAS, ASA, RHS

Valid congruence criteria are: SSS (Side-Side-Side), SAS (Side-Angle-Side), ASA (Angle-Side-Angle), AAS (Angle-Angle-Side), and RHS (Right angle-Hypotenuse-Side). AAA only ensures similarity, not congruence. SSA is not a valid criterion as it can lead to ambiguous cases.

2multiple choice

The exterior angle of a triangle is 120°. If one of the interior opposite angles is 50°, find the other interior opposite angle:

Show answer

70°

By the exterior angle theorem, an exterior angle equals the sum of the two non-adjacent interior angles. So: Exterior angle = Sum of two opposite interior angles. 120° = 50° + other angle. Therefore, other angle = 120° - 50° = 70°.

3multiple correct

If triangle ABC ≅ triangle PQR, and AB = 5 cm, BC = 7 cm, which of the following must be true?

Show answer

PQ = 5 cm, QR = 7 cm, ∠A = ∠P, Area of ABC = Area of PQR

When triangles are congruent (ABC ≅ PQR), corresponding parts are equal: AB = PQ = 5 cm, BC = QR = 7 cm, ∠A = ∠P, ∠B = ∠Q (not ∠R), ∠C = ∠R. Congruent triangles have equal areas.

4multiple choice

A triangle can have at most how many obtuse angles?

Show answer

1

A triangle can have at most one obtuse angle. If a triangle had two obtuse angles, their sum would exceed 180° (since each obtuse angle > 90°), but the sum of all three angles in a triangle must be exactly 180°. Therefore, maximum one obtuse angle is possible.

+36 more questions available

Practice All

Frequently Asked Questions

What are the important topics in Triangles for ICSE Class 9 Mathematics?
Triangles covers several key topics that are frequently asked in ICSE Class 9 board exams. Focus on the core concepts listed on this page and practise related questions to build confidence.
How to score full marks in Triangles — ICSE Class 9 Mathematics?
Understand the core concepts first, then work through the 40 practice questions available for this chapter. Revise formulas and 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

All 28 chapters — ICSE Class 9 Mathematics Practice Quiz

For serious students

Get the full Triangles chapter — for free.

Quizzes, flashcards, AI doubt-solver and a step-by-step study plan for ICSE Class 9 Mathematics.

Try Super Tutor Free
Try the full chapter — Free