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Chapter 9 of 28
Formula Sheet

Triangles — Formula Sheet

ICSE · Class 9 · Mathematics

5 formulas from Triangles (ICSE Class 9 Mathematics) on one page, grouped by topic. Part of the ICSE Class 9 Mathematics syllabus.

40 questions30 flashcards5 formulas & key relations5 concepts

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A labeled diagram showing the vertices, sides, and angles of a basic triangle ABC.
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One of 13 illustrations for Triangles in Super Tutor — alongside flashcards, concept maps and practice questions.

5 Entries · 2 Sections

Formulas and Key Relations

Angle sum and exterior angle

∠A + ∠B + ∠C = 180°

Exterior angle at A = ∠B + ∠C

Centroid and orthocentre

AG : GD = 2 : 1

BG : GE = 2 : 1

CG : GF = 2 : 1

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Frequently Asked Questions

What are the important topics in Triangles for ICSE Class 9 Mathematics?
Key topics in Triangles include Basic Ideas and Side-Angle Relations, Medians, Centroid, Altitudes and Orthocentre, Angle Sum, Exterior Angles and Corollaries, Congruent Triangles and CPCTC. Study these first, then practise questions on each for Class 9 exams.
How many formulas are in Triangles?
This sheet lists 5 formulas from Triangles, grouped by topic. Learn what each symbol stands for so you can apply the formula, not just recall it.
How should I revise Triangles for Class 9 exams?
Learn the core ideas first, then work through the 40 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

All ICSE Class 9 Mathematics Formula Sheet

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