Math Linear equations Linear equation

# Linear equation

Every linear equation has a variable $x$ that does not occur in any higher power (for example, $x^2$ or $x^3$). A linear equation can have one, two or more unknowns. The general form for a linear equation with one variable is:

$ax+b=0$

$a$ and $b...$ real numbers
$x ...$ unknown variable

i

### Tip

Most often, the variable is denoted by $x$ in linear equations. Note, however, that even equations with other letters can be linear equations.

### Examples

• #### Linear equations (with one variable)

$3x+15=0$
$5x+3=0$
$7b=14$
• #### No linear equations

x occurs at a higher power (e.g. $x^2$ or $x^5$)
$x^2+4=29$
$5x^5+12y+18=0$