# The nine-point circle

- Author:
- Andrew Dales

- Topic:
- Circle

This diagram shows the famous "nine point circle" and Euler's line. The centres are:

- The Circumcentre (O)
- The Orthocentre (H)
- The Centroid (G)
- The nine-point centre (N)

Try moving the points A, B and C. What do you notice about the points H, N, G and O? Can you prove that this is always the case?