We can clearly see two points A and B, we can freely move these two points. We will observe how the distance between these two points changes as we move these two points. Distance AB is written with the line segment AB. We have drawn perpendiculars to x axis and y axis by the points A and B.

Questions to think about.
1. What do you observe when these two points A and B lie on a same horizontal line. For hint- relation between coordinates and distance between these two points
2. What do you observe when these two points A and B lie on a same vertical line. For hint- relation between coordinates and distance between these two points
3. Have you seen any right angled triangle in the figure? Try to get distance between these two point using Pythagoras theorem