Description

Simply stated, a linear equation is an equation where variables are only multiplied by constants. No variable is multiplied by another variable or by itself. Therefore, each linear equation can be written in the following form, where $x_1, x_2, \ldots, x_n$ are independent variables and $a_1, a_2, \ldots, a_n, b \in \mathbb{R}$:

$a_1x_1 + a_2x_2 + a_3x_3 + \cdots + a_nx_n = b$