Final answer:
Supply curves in economics are most commonly drawn as straight lines, which demonstrate that as price increases, the quantity supplied also increases.
Step-by-step explanation:
To simplify analysis in economics, supply curves are often drawn as straight lines. Although the true supply curve for a product could be curved, steeper, or flatter, for ease of analysis and instruction, the supply curve is commonly represented as a straight line that slopes upward from left to right. This representation demonstrates the law of supply: as the price increases, the quantity supplied also tends to increase, and vice versa.
In economic graphs, both supply and demand curves appear with the price on the vertical axis and quantity on the horizontal axis. The point where these curves intersect is known as the equilibrium, indicating the price at which the quantity demanded equals the quantity supplied.