System of linear equations and inequalities

Introduction

Two or more linear equations together form a system of linear equations.

The following is a system of linear equations in two variables, $x$ and $y$:

$2x-y=3$

$3x+2y=8$

Sections in this chapter

Solution of a system of equations

What a solution of a system of equations is, and how to verify one.

Graphical method

Finding the solution as the intersection of the graphs, including no-solution and infinite-solution cases.

Substitution method

Solving a system by solving for one variable and substituting.

The elimination method

Solving a system by eliminating a variable through addition.