The x-coordinate is the first coordinate in an ordered pair. Coordinates are a pair of numbers for which the order is important. Coordinates are the numbers that give the location of a point in a plane such as (3, 1). The order of the numbers in the pair is important because the point (1, 3) is not the same as the point (3, 1). The first number in the ordered pair is called the abscissa and the second number is the ordinate. The x-coordinate (independent variable) is listed first, and the y-coordinate (dependent variable) listed second. In the graph below, notice how the point on the plane changes when the x-coordinate changes from 3 to 1.