Review of Graphing Points
Graphing Points
Points are graphed on the Cartesian Coordinate System using ordered pairs. Each ordered pair has an x coordinate and a y coordinate. In the coordinate pair (3,4), 3 is the x coordinate and 4 is the y coordinate. To graph the point (3,4), we would go 3 units to the right on the x axis and 4 units up “the ladder” of the y axis. Here is a video to refresh yourself on how to graph points:
[1] "Coordinate System - Plotting Points"
[2] "Graphing Relations"
Relations of Graphs
Graphs can have different relations which describe their behavior.
- A graph has a direct relation or a positive relation when the y value increases as the x value increases.
- A graph has an inverse relation or a negative relation when the graph curves downward and the y value decreases as the x value increases.
- An indirect relation, another kind of negative relation is an inverse relation that is straight. A graph has a zero relationor constant relation when the y value stays constant as the x values increases.
- A graph has a curvilinear relation when the y value increases and decreases the x values increases.
- A graph has a cyclic relation when it goes up and down repeatedly.
- A graph may be random, but before we determine that a graph is random we need to make sure that there is no equation which fits it well. We will learn about different kinds of equations that create different kinds of graphs.
- A graph has a zero relation or a constant relation when y does not increase or decrease as x increases.
Test Yourself
On a piece of graph paper, graph each set of points and determine the relation of the graph:
1. (1,2), (2,4), (4,8)
2. (2,1), (4,2), (8,4)
3. (0,1), (1, 0), (2,1), (3,0)