Given that the vectors `vec(a) and vec(b)` are non- collinear, the values of x and y for which the vector equality ` 2 vec(u) -vec(v)= vec(w)` holds true if `vec(u) = x vec(a) + 2y vec(b), vec(v)= - 2 y vec (a) + 3 x vec(b), vec(w) = 4 vec(a)-2 vec(b) ` are