The Cartesian plane, named after the French mathematician René Descartes, is the grid-like framework on which the coordinate system is laid out. It’s like a canvas where we plot our numerical data. The plane is divided into four quadrants by the intersection of the x-axis and y-axis.
Each quadrant contains points with specific sign combinations:
- Quadrant I: Both x and y coordinates are positive.
- Quadrant II: x is negative, y is positive.
- Quadrant III: Both x and y coordinates are negative.
- Quadrant IV: x is positive, y is negative.
Points on the axes themselves are not considered to be in any quadrant. A key to mastering the Cartesian plane is to understand these sign patterns, as they allow you to quickly determine the position of any point just by looking at its coordinates.