How do I go about solving this differential equation?

I can't remember if we even covered this in my calculus class, but as soon as I see the solution it should jog my memory.

$\displaystyle 0 = 4\frac{dy}{dx} + x\frac{d^{2}y}{(dx)^{2}} \quad \text{where} \quad y=f(x)$

Thanks again!