y = f(x)
Sometimes, instead of seeing the typical y = mx + b equation, or something similar, you’ll see f(x) =
mx + b. Look familiar? Graphs are just another way to show information from a function. Functions
show information algebraically and graphs show functions geometrically (as pictures).
Here’s an example. The function f(x) = 3x − 2 is shown graphically as the following:
The reason the SAT includes function questions is to test whether you can figure out the relationship
between a function and its graph. To tackle these questions, you need to know that the independent
variable, the x, is on the x-axis, and the dependent variable, the f(x), is on the y-axis. For example, if