Graphs
Introduction
Graphs are a graphic representation of quantitative data such as a table or
chart. A graph, or chart, conveys information, data, and statistics for
comparison, analysis, and prediction. Graphs are easier to understand than a
table of text and figures. The graphs covered in this segment are rectangular
coordinate graphs, bar graphs, line graphs, percentage bar graphs, and pie
charts.
Rectangular
coordinate
graphs
Rectangular coordinate graphs show the relationship between two or more
variables. You can plot a large number of points and compare their related
curves to show overall trends as opposed to absolute quantities. These points
or coordinates reflect quantities in relation to a given reference frame.
Reference
frame
y- axis and x-axis is the coordinate 0, (0,0), or origin. This intersection
creates four quadrants, numbered counterclockwise I, II, III, and IV. The
following table lists the value of each quadrant:
A reference frame of a rectangular coordinate graph is a vertical and a
horizontal line that intersect at a 90-degree angle. The vertical line is the
y-axis and the horizontal line is the x-axis. The point of intersection of the
Quadrant
Value
Quadrant I
Positive values along each axis.
Quadrant II
Negative x-axis values, positive y-axis values.
Quadrant III
Negative values along each axis.
Quadrant VI
Positive x-axis values, negative y-axis values.
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