Prove or disprove that the following are equivalence relations. If you find one
(or both that is an equivalence relation, write the equivalence class of any one element of your choice.
(a) For a, b, c. d € Z with b, d # 0: (a, b)R(c.d) # ad = be.
(b) For X,Y € R: R= {(r.y) : ×+ y= 31.