How to remeber this on the test

Required information Exercise 7-17A Record the sale of equipment (LO7-6) [The following information applies to the questions displayed below.) Abbott Landscaping purchased a tractor at a cost of $33,000 and sold it three years later for $16,500. Abbott recorded depreciation using the straight-line method, a five-year service life, and a $2,000 residual value. Tractors are included in the Equipment account. Exercise 7-17A Part 2 2. Assume the tractor was sold for $10,300 instead of $16,500. Record the sale. (If no entry is required for a particular transaction/event, select "No Journal Entry Required" in the first account field.) Answer is not complete. No Transaction General Journal Credit Cash Debit 16,500 18,600 Accumulated Depreciation Gain Equipment 2,100 33,000