Graphing calculators come in different sizes, with different functions and from different companies, but for all graphing calculators the method of creating a graph is fundamentally the same. Regardless of the type of function you wish to graph, creating a graph on a graphing calculator involves specifying the equation of your graph, setting up the calculator to prepare to display your graph and calling the graph function of your calculator to display the graph. After the creation of the graph, you have the ability to analyze the graph with the various functions of your graphing calculator.
Find and enter the "plot function" screen. This screen is a list of equations, starting with “y =” that allows you to finish the equation. You can find this screen through the menu list on your calculator. Many graphing calculators make this screen easily accessible by having a button labeled “y =” near the top of the calculator.
Enter the function you wish to graph. Because the “y =” part of the equation is already taken care of by the calculator, you need only enter the remaining part of the equation. This remaining part usually includes a variable. Graphing calculators require you to use “x” as the variable, because the default axes of graphing are the x-axis and y-axis. Enter your equation with the number buttons as well as the “x variable” button. For example, if you wish to graph the equation “y = x – 3,” press “x variable,” "-" and “3.”
Find the graphing window screen. This screen allows you to determine the length of the x and y-axes. Many graphing calculators allow access through this screen with a button labeled “window.”
Set up the size of the graphing window. Many functions can only be seen through the creation of an appropriate window size. For example, the graph “y = 100” cannot be seen if the window size does not allow the y-axis to extend beyond 100. When you know where the axes should begin and end for the graph, enter the values into the four spaces labeled “y-min,” “y-max,” “x-min” and “x-max.” For example, when graphing “y = x - 3” you should assure that the y-axis goes beyond -3 so that you can see the y-intercept. Enter a value below -3 for “y-min” and whatever you like for the other three spaces.
Call the graph function. Press the “graph” button to display the graph.