here the student needs to use both implicit differentiation and the product rule.
I would differentiate term by term for this problem.
for 2ye^-3x you have to use the proudct rule. uv differentiates to uv' +u'v
so the above differentiates to -6ye^-3x +2(dy/dx)e^-3x
-x differentiates to -1
4 is a constant so differentiates to 0.
leads to ; -6ye^-3x +2(dy/dx)e^-3x -1=0
which can be written as 2(dy/dx)e^-3x = 6ye^-3x +1
leads to dy/dx= (6ye^-3x +1)/2e^-3x =(e^3x)/2 + 3y