9Y/T Band: Unit: Angles in polygons

1. Interior angles in a triangle

In this lesson, you will learn about the interior angles in a triangle, and how to find unknown angles in various types of triangles.

2. Categorising and defining polygons

In this lesson, you will learn about the key terminology involved in describing polygons, and begin to categorise polygons, based on certain properties.

3. Building shapes from triangles (Part 1)

In this lesson, you will learn how to arrange triangles to form polygons (part I).

4. Building shapes from triangles (Part 2)

In this lesson, you will learn how to arrange triangles to form polygons (part II).

5. Polygons and triangles

In this lesson, you will learn that the sum of the interior angles of a polygon can be found using triangles.

6. Generalising angles in polygons (Part 1)

In this lesson, you will learn how to generalise the sum of the interior angles in an n-sided polygon.