When the price of commodity A increases, the demand for commodity B decreases, then A and B are
Answer Details
If an increase in the price of commodity A leads to a decrease in the demand for commodity B, then A and B are complementary goods. Complementary goods are those that are typically consumed together. When the price of one of the goods goes up, it becomes more expensive to consume both goods, leading to a decrease in the demand for the other. For example, if the price of gasoline (commodity A) goes up, people may reduce their driving, leading to a decrease in the demand for cars (commodity B).