How to Solve a Non-Separable Differential Equation?

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To solve the non-separable differential equation dy/dx = -(4x+4y) / (4x+4y-2), the substitution v = x + y is suggested. The correct derivative is dv/dx = 1 + dy/dx, which was initially miswritten. After reevaluating the steps, the solution leads to the answer -((x+y)^2) + (x+y) = x + A. The participant confirmed they understood the solution after correcting their approach.
hotjohn
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Homework Statement


i was given dy/dx = -(4x+4y) / (4x+4y-2) , v= x +y . I have tried to do ( as in the photo) , but I didn't get the ans , in the last line of my working , the V and x are not separable , which part of my working is wrong ?

Homework Equations

The Attempt at a Solution

 

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If v = x+y, then dv/dx = 1 + dy/dx, not x + dy/dx as you wrote.
 
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phyzguy said:
If v = x+y, then dv/dx = 1 + dy/dx, not x + dy/dx as you wrote.
i have redone the question , but i gt stucked here , how to proceed?

btw , the ans given is - ( (x+y) ^2 ) +(x+y ) = x +A
 

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Check your signs again.
 
phyzguy said:
Check your signs again.
ok , i gt it correct now , thanks
 
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