Section P.1 – Graphs and Models
How to Graph xy Make a table to graph y = x Use your knowledge of relations and functions to make sure you pick values of x that make a complete graph You do not need to plot every point, but make sure to get the complete graph. Only use a ruler if the relation is linear.
Definitions x-interceptWhere the graph crosses the x-axis OR The value of x when y is 0. y-interceptWhere the graph crosses the y-axis OR The value of y when x is 0.
Types of Symmetry With Respect to the… y-axisx-axisorigin Tests… Replacing x in the equation by –x yields an equivalent equation. Replacing y in the equation by –y yields an equivalent equation. Replacing x in the equation by –x and y by –y yields an equivalent equation.
Example of Symmetry Test for symmetry in the equation. Check out the graph first. Test by Replacing x in the equation by –x. The equation is symmetric with respect to the y-axis. An equivalent equation.
System of Equations Example Solve the following system of equation algebraically: Both equations equal y. Set them equal to each other.
System of Equations Example Solve the following system of equation algebraically: No Solution. FALSE The two lines are parallel. They never intersect.
System of Equations Example Solve the following system of equation algebraically: