Final answer:
The sale of machinery at a loss that was used in a trade or business and held for more than one year results in a §1231 loss, which is treated as an ordinary loss and can be used to offset other types of income.
Step-by-step explanation:
The sale of machinery at a loss that was used in a trade or business and held for more than one year results in a §1231 loss. §1231 is a tax code section that deals with the tax treatment of gains and losses on the sale or exchange of certain business assets. A §1231 loss is treated as an ordinary loss, which means it can be used to offset other types of income, such as salaries or interest.