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GR.9.2

Find the short side in a right-angled triangle

Calculate the length of a shorter side in a right-angled triangle

4 hand-picked video lessons for this topic, each checked for relevance and clarity, graded by difficulty and labelled by depth. Press play to watch — nothing loads from YouTube until you do.

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Grade 4–7 Core 🇬🇧 UK

Key Skill - Use Pythagoras' theorem to calculate a shorter side of a right-angled triangle.

Dr Frost Maths 33K views

Dr Frost shows exactly how to subtract to find a shorter side with Pythagoras.

Grade 3–6 Recap 🇬🇧 UK

Pythagoras Theorem | GCSE Maths 2025

Matt | MyGCSEMaths 51K views

Quick GCSE recap of finding a non-hypotenuse side using Pythagoras.

Grade 3–7 Core 🇬🇧 UK

Pythagoras - Corbettmaths

corbettmaths 482K views

Corbettmaths explains using Pythagoras to find missing sides, including shorter sides.

Grade 3–6 Core 🇬🇧 UK

GCSE Maths - Pythagoras' Theorem And How To Use It (2026/27 exams)

Cognito 538K views

Polished Cognito intro to Pythagoras' theorem and the a²+b²=c² method you rearrange for a short side.

Jump to 1:00The Formula: a² + b² = c² 1:11Labelling the Sides 1:50Example 1: Calculating the Hypotenuse (Integer Sides)2:34Example 2: Calculating the Hypotenuse (Decimal Sides & Calculator)