A line segment has been drawn onto a Cartesian coordinate grid system. Grab and move the endpoints of the line segment. They will only move to integer values and their coordinates are updated in the window at the bottom of each page. There is an option to use either a single quadrant coordinate system or a four quadrant coordinate system
You can choose either to place a midpoint onto the line segment and show its coordinates or use the pages where midpoint has been pre-constructed. Now, as you grab and move the endpoints, take a note of the coordinates of the endpoints and midpoint onto the associated worksheet and see if you can spot a relationship.