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: