# 2D Coordinate Geometry

###### This wiki is incomplete.

## Introduction

**2-dimensional coordinate geometry** involves assigning each and every point in 2-dimensional space with coordinates which can be uniquely used to identify the point. The coordinates are measured with respect to two mutually perpendicular reference lines, known as the coordinates axes.

## Coordinate axes and coordinates

The coordinate axes are commonly referred to as the $x$-axis and $y$-axis. The coordinates of the points are denoted as $(a,b) ,$ where $a$ is known as the $x$-coordinate or the abscissa. It is equal to the distance of the point from the $y$-axis (or vertical axis). $b$ is known as the $y$-coordinate or the ordinate. It is equal to the distance of the point from the $x$-axis (or horizontal axis).

**Cite as:**2D Coordinate Geometry.

*Brilliant.org*. Retrieved from https://brilliant.org/wiki/2d-coordinate-geometry/