Final answer:
Solubility rules are used to predict double-displacement reactions in chemistry.
Step-by-step explanation:
The type of reaction that must be predicted using solubility rules is a double-displacement reaction. Solubility rules are used to predict whether certain ionic compounds will dissolve in water or form a solid precipitate. In a double-displacement reaction, the cations (or the anions) of two ionic compounds exchange places, resulting in the formation of new compounds.