Using the numbers 1-6, the solution is 3x6y5/(x4y2)=3x2y3 or 6x5y4/(2x3y)=3x2y3.
a=3, b=6, c=5, d=1, e=4, f=2; or a=6, b=5, c=4, d=2, e=3, f=1.
Because:
a=3d, b-e=2, c-f=3 equating coefficients and powers.
If we only use numbers 1-6, then (a,d) can only be (3,1) or (6,2).
If (a,d)=(3,1), then (c,f)=(5,2) and (b,e)=(6,4)
If (a,d)=(6,2), then (c,f)=(4,1) and (b,e)=(5,3)