Differential Equation, nonlinear, nonexact

MeMoses
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Homework Statement


\frac{dy}{dx}=\frac{2y - x + 7}{4x - 3y -18}


Homework Equations





The Attempt at a Solution


I tried using v = y/x and got nothing. Same goes for trying to find an integrating factor to make the equation exact. I am given a hint, Find h and k so that the substitution x = u+h, y=v+k transforms the above to a homogenous differential equation. I'm not sure what the means or how I'm supposed to use that. Thanks for any help.
 
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MeMoses said:

Homework Statement


\frac{dy}{dx}=\frac{2y - x + 7}{4x - 3y -18}


Homework Equations





The Attempt at a Solution


I tried using v = y/x and got nothing. Same goes for trying to find an integrating factor to make the equation exact. I am given a hint, Find h and k so that the substitution x = u+h, y=v+k transforms the above to a homogenous differential equation. I'm not sure what the means or how I'm supposed to use that. Thanks for any help.

Do you see why the v = y/x method didn't work? Do you see why the ##\frac{M(x,y)}{N(x,y)}## functions aren't homogeneous? Can you use the given substitution to get rid of the 7 and -18?
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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