To solve an inequality, simplifiy using the properties of equality (using the same operation on both sides of the inequality sign) until you get the variable by itself.
2x < 12, then divide both sides by 2 to get
x < 6
This gives us three things to graph: A position (6), a dot (open because there's no equality line under the "less than" symbol), and a direction (to the left, the same way that the "less than" sign points).
When you are solving an inequality and you multiply or divide by a negative number, the negative sign causes the position and the direction to become opposites. Multiplying or dividing by the negative sign "flips" the sign of the number and it also "flips" the direction of the thick bar and arrow in the graph.
-2x < 12, then divide both sides by -2 to get
x > 6, having changed the direction of the inequality from pointing left to pointing right.
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