GMAT Maths Algebra - Inequalities

Solving inequalities is very similar to solving equations. The four symbols used when solving inequalities are
as follows:
? is less than
? is greater than
? is less than or equal to
? is greater than or equal to
When solving inequalities, there is one catch: If you are multiplying or dividing each side by a negative
number, you must reverse the direction of the inequality symbol. For example, solve the inequality
–3x + 6 <= 18:

1. First subtract 6 from both sides: -3x + 6 -6 <= 18 - 6
2. Then divide both sides by –3: -3x/-3x <= 12/-3
3. The inequality symbol now changes: x >= -4