Understanding how to find missing angles in triangles is a...
Maths96 views·Updated 16 Jul 2026·1 pageFinding the Missing Angles of a Triangle
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Danielle Kurlin@anielleurlin_sz5q2fx
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Finding Missing Angles in Triangles
Ever wondered how mathematicians work out mystery angles? It's actually dead simple once you know the golden rule: angles in a triangle always add up to 180°.
In this example, we've got two known angles (52° and 59°) and need to find the third angle 'a'. First, we add the known angles together: 52° + 59° = 111°. Then we subtract this total from 180° to find our missing angle.
The calculation looks like this: a = 180° - = 180° - 111° = 69°. Notice how we use brackets to make sure we add the known angles first before subtracting from 180°.
Quick Check: Always verify your answer by adding all three angles together - they should equal exactly 180°! In this case: 52° + 59° + 69° = 180° ✓
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Maths96 views·Updated 16 Jul 2026·1 pageFinding the Missing Angles of a Triangle
D
Danielle Kurlin@anielleurlin_sz5q2fx
Understanding how to find missing angles in triangles is a crucial skill that you'll use constantly in GCSE maths. This example shows you the step-by-step process using the fundamental rule that all angles in a triangle must add up to...
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Finding Missing Angles in Triangles
Ever wondered how mathematicians work out mystery angles? It's actually dead simple once you know the golden rule: angles in a triangle always add up to 180°.
In this example, we've got two known angles (52° and 59°) and need to find the third angle 'a'. First, we add the known angles together: 52° + 59° = 111°. Then we subtract this total from 180° to find our missing angle.
The calculation looks like this: a = 180° - = 180° - 111° = 69°. Notice how we use brackets to make sure we add the known angles first before subtracting from 180°.
Quick Check: Always verify your answer by adding all three angles together - they should equal exactly 180°! In this case: 52° + 59° + 69° = 180° ✓
We thought you’d never ask...
Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.
You can download the app from Google Play Store and Apple App Store.
That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.
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Most popular content: Missing Angle Problems
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Prepare for your GCSE Higher Mathematics exam with this comprehensive mock exam set. This resource covers key topics such as simplifying rational expressions, solving inequalities, geometric transformations, and more. Ideal for students looking to practice and improve their understanding of essential mathematical concepts. Includes detailed solutions and explanations for each question.
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