Assume That the Demand for a Specific Tablet Computer (X) $$Q d _ { X } = 2000 - 20 P _ { X } + 10 P _ { Y } - 20 P _ { Z }$$

Essay

Assume that the demand for a specific tablet computer (X) is represented by the following equation:
$$Q d _ { X } = 2000 - 20 P _ { X } + 10 P _ { Y } - 20 P _ { Z }$$ Which of the products Y and Z is a substitute to tablet computer? Which of the products is a complement?