(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

dy/dx = (x+3y)/(3x+y)

I have to solve the given differential equation by using an appropriate substitution...

3. The attempt at a solution

I used algebra to make the equation (3x+y)dy - (x+3y)dx = 0

then made x = vy and dx = vdy + ydv.

then plugged in to get (3vy+y)dy - (vy+3y)(vdy+ydv)

and now I'm looking for a common factor to cancel and I'm stuck, any help? Am I even headed in the right direction...thanks.

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# Homework Help: Ordinary Differential Equation by substitution.

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