Question

show that the set M= \[{9a,b,c,d) ; a,b,c,d \in Q} \] with addition and multiplication define by (a,b,c,d)+(e,f,g,h)=(a+e,b+f,c+g,d+h). (a,b,c,d)(e,f,g,h)=(ae +bg,+af+bh,ce+dg,cf + dh) for all (a,b,c,d),(e,f,g,h) in M. is a ring