Let m be the larger integer.
(1/m) -[6/(m-4)] = -9/10
Clear fractions and collect terms: 10(m-4-6m) = -9m2 + 36m
9m2 -86m - 40 = 0
The quadratic formula gives an extraneous negative root and m = 10; then m-4 = 6
You should should check that these values solve your original problem.
BTW, I think these are the only values which solve the problem as stated.