Define complementary goods.

Complementary goods are defined as two or more goods that are consumed together to satisfy a single want or need. These goods are interdependent, meaning the demand for one good directly influences the demand for the other.

For example, bread and butter are complementary goods because they are typically consumed together. If the price of bread increases, the demand for butter is likely to decrease, and vice versa. Similarly, cars and petrol, television and cable connection, and smartphones and mobile data are other examples of complementary goods.

The relationship between complementary goods is negative—an increase in the price of one good leads to a decrease in the demand for its complementary good, and vice versa. This inverse relationship is a key characteristic of complementary goods in economics.