Look at pic for question and answers.

It is decreased by the sale amount

Explanation:

An income statement is a financial statement that communicates a business's profitability. An income statement lists the revenues and expenses incurred by a business in a period.

The sale of a company's asset may result in a loss or profit. A profit is treated as an income to the business, but a loss is an expense. When an asset is sold at a loss, business expenses increase. An increase in expenses reduces profits as reported in the income statement.

u = 30

continuing your method

= +

subtract from both sides

= - thus

= -

= ⇒ u = 30