**Co-ordinate Geometry** (also called Analytical Geometry), or Cartesian geometry, is the study of geometry using a cartesian coordinate system in two (and three also) dimensions. In the cartesian coordinate system, each point has an x-coordinate representing its horizontal position (x axis), and a y-coordinate representing its vertical position (y axis). Thus, every point is typically written as an ordered pair (x, y).

### Distance Formula

The distance between two points (x_{1}, y_{1}) and (x_{2}, y_{2}) is given by the formula:

### Midpoint Formula

The formula for determining the midpoint of a line segment with endpoints (x_{1}, y_{1}) and (x_{2}, y_{2}) is: