Sets And Relations

Let \(A=\{2,3,6,8,9,11\}\) and \(B=\{1,4,5,10,15\}\). Let \(R\) be a relation on \(A \times B\) defined by
\((a, b) R(c, d)\) if and only if \(3 a d-7 b c\) is an even integer. Then the relation \(R\) is