The inequality is .

Apply multiplication property of inequality: Multiply each side by 2.

             (Cancel common terms)

                   (Multiply )

     (Multiply each side by negative one and flip the symbol)   

                          (Product of two same signs is positive)

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 20, a number greater than 20, in .

                       (Substitute: x = 20)

                            (Divide: )

The inequality is true.

The inequality solution is .