When you have a ratio of two things, you can multiply both that top and the bottom by the same quantity and maintain the equality. Think about what you can multiply (or divide) the top and bottom by to get it in the correct form.
You are right I made an error which might look trivial in itself but made the end result wrong. In L7 I had In(x) but while doing a calculation on the equation of L7 I instead wrote In(|x|) which is responsible for the error. I believe the correct solution is:
As you can see here, there are two formulae given for homogeneous equation, 18.5 and 18.6. The form of the homogeneous differential equation I have encountered often so far is the 18.5 one. I see for 18.6 form, we have to take v=xy instead of v=y/x as was the case for the 18.5. I was searching for some example problem which uses the formula 18.6 but wasn't successful. Could you please help? Thanks.