Final answer:
Demand is unit elastic when a change in price leads to an equal change in quantity demanded.
Step-by-step explanation:
Constant unitary elasticity occurs when a price change of one percent leads to an equal percentage change in quantity demanded.
For example, if the price of a product increases by 10%, and as a result, the quantity demanded decreases by 10%, then the demand is unit elastic. This means that the percentage change in price equals the percentage change in quantity, resulting in an elasticity of 1.
Unit elasticity can be represented by a demand curve with a curved shape, where the slope is steeper on the left and flatter on the right as you move along the curve.