The inequality is .

Apply Subtraction property of inequality: Subtract 1 from each side.

               (Apply Additive inverse property: )

                       (Apply Additive identity property: )

                             (Subtract: )

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 greater than or equal to – 9 in .

                 (Substitute )

                       (Add: )

The inequality is true.

The inequality solution set is .