Hello, Im having problems with equivalence classes.

The relation R is defined for complex numbers z=x+yi and w=a+bi. zRw if and only if x+b=y+a

I am asked to give the elements of the equivalence class containg [i]

I have wrote, [i]={xeC:xRi}={xeC:x-i} to begin finding the equivalence classes, but am stuck trying to find the elements