Areas of Triangles Using Trigonometry – Complete Lesson

This is a complete lesson on areas of triangles using trigonometry that looks at how to calculate the area of any triangle. The lesson is designed with the new GCSE specification in mind.

Lesson Objective

  • To know and apply Area = 1/2 ab sin(C) to calculate the area, side length or angles of any triangle.

Who is this Lesson For?

This pack is designed for GCSE higher tier students. It could also be used with high ability Key Stage 3 students.

What is Included?

Included in this download are the following:

  • Full lesson plan for the ‘Areas of Triangles Using Trigonometry’ lesson, including introduction, teaching content, individual activities, plenary and suggested support and extension activities
  • Areas of Triangles Intro
  • Demonstration Slide
  • Area of Triangles Example Slide
  • Area of Triangles Mini-Plenary
  • Finding Unknown Side Example Slide
  • Finding Unknown Angle Example Slide
  • Mini-Plenary
  • Student Worksheet on Areas of Triangles Using Trigonometry
  • Plenary Cards
  • Further Trigonometry Fact Sheet
  • Complete Solutions to all Questions

Lesson Progression

This is the first lesson in the Further Trigonometry unit of work (the unit is also available as a pack including homework activities and a unit assessment).

The other lessons in the unit are: