Question

what is the electronic configuration of x and y

Answer 1

X has got 3 valence electrons. It'll lose all 3 and each one of them will be picked up by the 3 Y each. Thus we have X with a +3 charge and 3Y with a -1 charge each. So, now X has electronic configuration as 2,8 and each of the Y have 2,8,8.

Answer 2

Hey mate!!!!
Ur question is incomplete....
As u must either tell the names of the elements or should tell the atomic number of x and y.... ☺️