A linear inequality is an inequality that represents a linear relationship involving one or more variables. Therefore, the exponent of all variables is $1.$ As with any other inequality, linear inequalities can be strict or non-strict.

Strict Linear Inequalities	Non-Strict Linear Inequalities
$\text{-}13>\text{-}2x+4y$	$7x-y\ge 21$
$\text{-}9y<17+x$	$9x+3y\le 6$

Linear inequalities are similar to linear equations. The difference is that, while the solutions to linear equations are represented by all the points that lie on a line, the solution set to a linear inequality is represented by the points on a region containing one half of the coordinate plane.