Skip to main content
Super TutorResources
Chapter 10 of 28
QuestionsNotesFlashcardsSummaryFormulasQuizConceptsSyllabusPlan
Chapter Summary

Isosceles Triangles

ICSE · Class 9 · Mathematics

Summary of Isosceles Triangles for ICSE Class 9 Mathematics. Key concepts, important points, and chapter overview.

35 questions20 flashcards5 concepts

Interactive on Super Tutor

Studying Isosceles Triangles? Get the full interactive chapter.

Quizzes, flashcards, AI doubt-solver and a step-by-step study plan — built for chapter summary and more.

Try Super Tutor — Free

1,000+ Class 9 students started this chapter today

A labeled diagram illustrating an isosceles triangle with two equal sides and the angles opposite to them also being equal. Includes the definition of an equilateral triangle as a special case.
Super Tutor

Super Tutor has 7+ illustrations like this for Isosceles Triangles alone — flashcards, concept maps, and step-by-step visuals.

See them all

Overview

An isosceles triangle is a triangle with at least two equal sides. An equilateral triangle has all three sides equal and always satisfies the properties of an isosceles triangle. The chapter develops the main facts of isosceles triangles through angle-side relationships and congruence proofs.

Key Concepts

A triangle

A triangle, with atleast two sides equal to each other, is called an isosceles triangle.

If all the sides of

If all the sides of a triangle are equal to each other, it is called an equilateral triangle. An equilateral triangle satisfies all the properties of

If two sides of a triangle

If two sides of a triangle are equal, the angles opposite to them are also equal. For triangle ABC with AB = AC, drawing AD perpendicular to BC helps

If two angles of a triangle

If two angles of a triangle are equal, the sides opposite to them are also equal. For triangle ABC with angle B = angle C, drawing AD perpendicular to

In an isosceles triangle

In an isosceles triangle, the two equal sides meet at the vertex, and the side opposite them is the base. The angles opposite the equal sides are the

Learning Objectives

  • Identify an isosceles triangle and an equilateral triangle.
  • Use the fact that equal sides of a triangle give equal opposite angles.
  • Use the converse fact that equal angles of a triangle give equal opposite sides.
  • Apply triangle congruence to prove results in isosceles triangles.
  • Use key properties of isosceles triangles to solve angle and length problems.

Frequently Asked Questions

What are the important topics in Isosceles Triangles for ICSE Class 9 Mathematics?
Isosceles 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 Isosceles Triangles — ICSE Class 9 Mathematics?
Understand the core concepts first, then work through the 35 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 Isosceles Triangles

All 28 chapters — ICSE Class 9 Mathematics Chapter Summary

For serious students

Get the full Isosceles 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