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The coordinate plane is a two-dimensional surface used to plot and identify points. It consists of a horizontal number line called the x-axis and a vertical number line called the y-axis.
Both the x-axis and the y-axis have a positive and negative side and both have a center at 0. The centers of the x- and y-axes intersect at a point in the coordinate plane called the origin. The origin is at 0 on both the x-axis and the y-axis.
The x- and y-axes divide the coordinate plane into four quadrants:
All points on the coordinate plane can be indicated by an x value and a y value. These two values form a coordinate pair, which is written as (x,y). The point at the origin is represented by the coordinate pair (0, 0).
Starting at the origin, the first coordinate indicates how far to move in the horizontal direction along the x-axis. The second coordinate indicates how far to move in the vertical direction along the y-axis.
The coordinate plane below illustrates different ordered pairs in each quadrant:
A scatterplot or scatter diagram is a certain type of graph. A scatter diagram is the collection of points on the coordinate plane used to represent data. Coordinate points in ordered pairs in scatter diagrams form a relationship between two variables.
Scatter diagrams are used to display various types of data in science, psychology, sociology, and statistics. Being able to read and interpret graphical information is important in these areas of study.
EXAMPLE
In the scatterplot below, the arm spans and heights of 10 people were measured, and the data was plotted on the scatter diagram. The x-axis represents the values of the x variable, arm span, which was measured in centimeters, and the y-axis represents the values of the y variable, height, which was also measured in centimeters. Each point on the graph represents the arm span and height for one person.Source: This work is adapted from Sophia author Colleen Atakpu.