Since the origin has an x-coordinate of 0 and a y-coordinate of 0, its ordered pair is written (0, 0). Note that the x-coordinate is listed before the y-coordinate. In an ordered pair, such as (x, y), the first value is called the x-coordinate and the second value is the y-coordinate. An ordered pair tells you the location of a point by relating the point’s location along the x-axis (the first value of the ordered pair) and along the y-axis (the second value of the ordered pair). Locations on the coordinate plane are described as ordered pairs. Quadrants are named using the Roman numerals I, II, III, and IV beginning with the top right quadrant and moving counter clockwise. These four sections are called quadrants. The intersecting x- and y-axes divide the coordinate plane into four sections. The origin is at 0 on the x-axis and 0 on the y-axis. The point at which the two axes intersect is called the origin. The horizontal axis in the coordinate plane is called the x-axis. It consists of a horizontal axis and a vertical axis, number lines that intersect at right angles. The coordinate plane has similar elements to the grid shown above. You’ll find a blue disc is at this location on the map. For example, you can find the item that exists at square 4 F by moving your finger along the horizontal to letter F and then straight down so you are in line with the 4. The general location of any item on this map can be found by using the letter and number of its grid square.

Notice that the letters A through F are listed along the top, and the numbers 1 through 6 are listed along the left edge. This “map” uses a horizontal and vertical grid to convey information about an object’s location. For example, have you ever used a gridded overlay to map the position of an object? (This is often done with road maps, too.) You have likely used a coordinate plane before.

Graphing pictures on a coordinate plane