The differential equation dydx=14+18x+14y+18xy

has an implicit general solution of the form F(x, y)=K.
F(x, y) = G(x) + H(y) = K.

In fact, because the differential equation is separable, we can define the solution curve implicitly by a function in the form
F(x, y)=G(x)+H(y)=K.

Find such a solution and then give the related functions requested.
F(x, y)=G(x)+H(y)