# Two-dimensional graph

Graph of the function $f(x)={{x^3}-9x} \!\$

A two-dimensional graph is the graph of a function of one variable f(x). Provided that x and f(x) are real numbers, the graph can be represented as a straight or curved curve in a two-dimensional Cartesian coordinate system.

## Example

The graph of the cubic polynomial on the real line

$f(x)={{x^3}-9x} \!\$

is

{(x, x3-9x) : x is a real number}.

If this set is plotted on a Cartesian plane, the result is a curve (see figure).