The inequality is

                 (Add: )

Apply subtraction property of inequality: Subtract 20 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 10 in inequality.

        (Substitute )

                        (Add: )

The inequality is true. 

The inequality solution set is .