1. 3-1 Inequalities and Their Graphs
Inequality: A mathematical sentence that uses an inequality symbol to compare the values of two expressions.
Solution of an Inequality: Any number that makes an inequality true.
Evaluate an expression to determine whether a value is a solution of an inequality.

2. 3-1 Inequalities and Their Graphs
You can use a number line to show all solutions of an inequality.
Graphing an Inequality:
Closed dot means the number IS a solution.
Open dot means the number is NOT a solution.
Shaded to the right on the number line means all numbers greater than the number are solutions.
Shaded to the left on the number line means all numbers less than the number are solutions.