The inequality is .

According to subtration  property of inequality: Subtract 18 from each side.

             (Apply commutative property of additin:  )

                       (Apply additive inverse property:  )

                              (Apply additive identity property:  )

                                    (Add: )

Graph the solution set on a number line.

Note: A dot means that this point is included in the solution set.

Check:

To check, substitute a number less than 3 in .

                          (Substitute  )

                                    (Add: )

The inequality is true.

The inequality solution set is .