Medians and centroid of a triangle

The centroid of a triangle is where the three medians intersect. This activity will show you how to find the centroid and you’ll explore several geometric relationships related to centroid and medians.

Objectives

To introduce medians of a triangle and their point of concurrence.

Estimated Time

30 minutes

Prerequisites/Instructions, prior preparations, if any

Types of triangles, their medians and their constructions should have been covered.

Materials/ Resources needed

• Digital : Computer, geogebra application, projector.
• Non digital : Worksheet and pencil.
• Geogebra files : Concurrency of medians.ggb

Download this geogebra file from this link.

Process (How to do the activity)

1. The teacher can use this geogebra file to show how the position of centriod is constant in different triangles.

• Developmental Questions:

1. Which type of triangle is this ?
2. What is a median ?
3. How do you identify the midpoint of the side ?
4. Which is the point of concurrency of medians of the triangle ?
5. Identify the position in different triangles.

• Evaluation:

1. What is the position of centriod in different triangles ?

• Question Corner:

1. Why do you think the centriod always remains in the centre for every type of triangle ?
2. What does the centriod indicate ?
3. What are the practical applications of the centriod ?