Here's the question you clicked on:
Deltaz
Differential equation solution : 2xy'-y=x+1
Well, you want an integrating factor. Do you know how to calculate it?
If not, I recommend watching this great lecture where the method of solving this equation is explained: http://ocw.mit.edu/courses/mathematics/18-03-differential-equations-spring-2010/video-lectures/lecture-3-solving-first-order-linear-odes/