Explain the economic value of a horizontal straight line price line for a firm

Dear Student
Horizontal straight line price line/revenue curve indicates that the price of the product is constant for a firm, or it is given to a firm. At the given price, a firm can sell any quantity. However, if the firm increases the price, it will sell nothing. It would lose all its buyers to other firms in the market. It implies that the elasticity of demand for the firm's product infinity. It is a situation of perfect competition in the market.
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