Loan is related to Equity. Stock is a type of Equity. Stock is a type of Support. 
Close is a type of Trade. Trade is related to Equal. Equal is related to Equality. Equality is a synonym of Equation. 
Loan <--RelatedTo--> Equity <--IsA-- Stock --IsA--> Support 
Close --IsA--> Trade <--RelatedTo--> Equal <--RelatedTo--> Equality <--Synonym--> Equation 