I am having a hard time trying to discover units sold at breaking point? I discovered on another assignment but can quite figure this one out.

Here is the problem:

Further analysis of Sutcliffe Industries's fixed costs revealed that the company actually faces annual fixed overhead costs of $9,800 and annual fixed selling and administrative costs of $4,200. Variable cost estimates are correct: direct materials cost, $4.80 per unit; direct labor costs, $6.00 per unit; and variable overhead costs, $1.20 per unit. At this time, the selling price of $40 will not change.