To solve for \(x\) and \(y\) in the equation \(\frac{dx}{dt} + \frac{dy}{dt}=a-(b+c+d)y-bx\), it is noted that there are two unknown functions but only one equation, limiting the ability to solve for both simultaneously. The discussion suggests finding one variable as a function of the other, potentially using substitution to simplify the process. The user has attempted to define variables \(U\) and \(V\) and is working through a method of plugging one into the other to derive a solvable equation. Additional context and resources have been shared to clarify the problem, indicating a need for further assistance. The conversation highlights the challenges of solving systems of linear ordinary differential equations with limited equations.