Hi

I suppose that x and y are integers

(x-y) being smaller than (x+y) the possibilities for ((x-y),(x+y)) are (1,36) ; (2,18) ; (3,12) ; (4;9) ; (6;6)

Their sum must be even because (x-y)+(x+y)=2x

Remain 2 possibilities

(2,18) => x=10 and y=8

(6,6) => x=6 and y=0