This is the fourth tutorial in the **GeoGebra Intermediate Tutorial Series**. If this is your first time to use GeoGebra, please read the **GeoGebra Essentials Series** first.

In this tutorial, we use GeoGebra to investigate the effects of parameters of the equations of functions to the appearance of their graphs. First, we type equations and then use a slider investigate the effects of .

**Graphing Functions**

- Open GeoGebra and be sure the the
*Algebra and Graphics*view is selected for the*Perspective*menu. - To graph , type
*y*= 2*x*in the*input field*. (The input field is the text box with the label*Input*located at the bottom of your GeoGebra window.) Press the**ENTER**key on your keyboard. - Type the following equations: y = 3x, y = 4x , y = -8x, and press the ENTER key after each equation.
- Type more equations of the form where is any real number.
- How does the value of affect the appearance of the graph of the function ?

**Using Sliders**

To avoid typing over and over again for varying values , we use the *slider* tool. A slider is a visual representation of a number. This time, we add the parameter *b*. This means that we will explore the graph of the function of , where and are real numbers.

**Instructions**

**Notes:**

- The ^ symbol is used for exponentiation. Hence, we write as a*x^2 + c.
- Instead of using in writing equations of functions, you can also use for the function .

**Last Update:** November 12, 2014 for GeoGebra 5.0.** **