# The Coordinate Plane Comprises 2 Axes and 4 Quadrants

By: Mitch Ryan  |

A coordinate plane is a mathematical, two-dimensional plane formed by two number lines. A horizontal number line and a vertical number line intersect to form two axes (plural for axis), and a grid system comprised of four quadrants.

Contents

## How Are Number Lines Orientated on Coordinate Planes?

Two number lines — one vertical and one horizontal — form the two-dimensional grid of a coordinate plane. These two axes intersect at a perpendicular angle (meaning it's 90 degrees), which forms four quadrants that create a space to locate points and graph values.

## 4 Quadrants of the Coordinate Plane

The central intersection, or origin point, of the coordinate plane lies at (0,0). The horizontal x-axis and the vertical y-axis provide a map for plotting points. Points lie on the lines or fall within one of four quadrants labeled with Roman numerals.

Quadrant I values are all positive numbers. Using a clockface as an illustration, the first quadrant of a coordinate plane lies between 12 and 3 o'clock. A plot point in this quadrant must have a positive x-coordinate to the right of the origin point (0,0) or a y-coordinate above the intersection.

Continuing counterclockwise, the second quadrant is between 12 and 9 o'clock. This quadrant requires a negative x-coordinate and a positive y-coordinate, moving left and up from the coordinate axes origin.

The third quadrant lies between 9 and 6 o'clock, or the bottom-left of the two-dimensional plane formed by number lines. Since this quadrant is comprised of a negative x-coordinate and a negative x-coordinate, plot points will fall below and to the left of the origin. All quadrant III values are negative numbers.

The final and fourth quadrant is comprised of values with a positive x-coordinate and a negative y-coordinate. This combination of positive and negative numbers falls below and to the right of the origin.