Final answer:
Good X has inelastic demand, good Y has elastic demand, and they are complements.
Step-by-step explanation:
The price elasticity of demand (PED) measures the responsiveness of quantity demanded to changes in price. A PED of 0.5 indicates an inelastic demand for good X, meaning that a percentage change in price will result in a less than proportional change in quantity demanded. This suggests that good X is a necessity or has limited substitutes.
The PED of 1.2 for good Y suggests that its demand is elastic. A percentage change in price will result in a more than proportional change in quantity demanded. This implies that good Y is a luxury or has many substitutes.
The negative cross-price elasticity of X and Y indicates that they are complements. A higher price for one good will lead to a decrease in the quantity demanded of the other good.