A system of linear equations is a set of two or more linear equations. To show that equations are part of the same system, they are usually written on top of each other and have a curly bracket to the left. It's not unusual to add Roman numerals, to be able to refer to the equations individually. Systems of linear equations often contain more than one unknown variable where the solution is the set of coordinates that make all equations true simultaneously. In the example above, the solution is $x=2$ and $y=1.$ These coordinates make the sides equal in both equations. The solution is usually written as a point: A system of linear equations can be solved both graphically and algebraically by using the substitution method or elimination method.