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Download Lesson Resources for Angles in a Triangle

Mr Mathematics membership Save hours of planning with the full lesson pack — includes presentation, worksheet and detailed solutions.

What's included in this lesson pack

  • Ready-to-teach PowerPoint presentation
  • Printable student worksheet
  • Scaffolded examples for progress and constant challenge
  • Exam-style questions
  • Answers for checking and feedback

Angles in a Triangle

 

Students learn how to work out missing angles in a triangle and on a straight line.

As learning progresses, they combine multiple-angle properties within a bigger problem.

Differentiated Learning Objectives
  • All students should be able to calculate the remaining angle in a scalene and right-angled triangle when given the two.
  • Most students should be able to use the properties of triangles to calculate angles in isosceles and equilateral triangles when given one.
  • Some students should be able to calculate angles in compound shapes involving multiple types of triangles.
Scheme of Work Links

Angle Properties Foundation

Angle Geometry Higher

Related Blog
Solving Problems with Angles in Parallel Lines

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