dy/dx +2y/x = 4x
find general solution
dy/dx= 4x + x/2y
2y dy = 4x + x dx
2y dy = 5x dx
integrate
y^2 = 2.5 x^2 + C
What you have done is not correct.
Your DE is not separable, you need to use the integrating factor method.
Do you know this method?
Read this http://www.mathhelpforum.com/math-he...equations.html