Equation is a synonym of Equality. Equality is related to Being. Being is related to Certain. Certain is similar to Reliable. 
Cake is related to Sweat. Sweat is related to Body. 
Equation <--Synonym--> Equality <--RelatedTo--> Being <--RelatedTo--> Certain <--SimilarTo--> Reliable 
Cake <--RelatedTo--> Sweat <--RelatedTo--> Body 