What is the graph of y = 2x ? A linear function is a function of f : ℝ→ℝ defined as **f(x) = a.x**, where **a** is a real number and **a ≠ 0. **All functions written as **f(x) = a.x** are written in the **standard form**.

## What is the linear function graph?

The graph of a linear function is a **straight line** that crosses the origin, thus, the point (0 ; 0). The **a** coefficient indicates the slope or steepness of the line. the higher de **a** coefficient, the more steep the graph line will be.

## How to plot the graph of y=2x linear functions?

To plot the graph of a linear function, it is necessary to know, at least, two points. One of the points is (0 , 0) and the other can be calculated, as the following example:

Given the function **f(x) = 2.x**

To be easier, one can build a table by giving values to** x** and calculate de values of **f(x)**, obtaining points to plot the graph. One point is already known, is the (0, 0) point.

if x = 1 then, f(x) = 2

Linear functions can be increasing ou decreasing. To know this, one just has to identify the signal of the **a** coefficient. If **a** is positive, the function will be increasing. If **a** is negative, the function will be decreasing.