Solve (3y + 2x + 4) * d * x - (4x + 6y + 5) * d * y = 0
"y'=\\frac{3y+2x+4}{6y+4x+5}\\\\\ny'=\\frac{3y+2x+4}{2(3y+2x)+5}"
substitute "3y+2x=z(x) \\to y=\\frac{z-2x}{3} \\to y'=\\frac{z'-2}{3}"
then
"\\frac{z'-2}{3}=\\frac{z+4}{2z+5}\\\\\nz'-2=\\frac{3z+12}{2z+5}\\\\\nz'=\\frac{7z+22}{2z+5}\\\\\n\\frac{2z+5}{7z+22}dz=dx\\\\\n\\frac{1}{7}\\int(\\frac{2(7z+22)-\\frac{22}{7} +35}{7z+22}dz=\\int dx\\\\\n\\frac{1}{7}\\int(2+\\frac{223}{7}\\cdot \\frac{1}{7z+22})dz=\\int dx\\\\\n\\frac{1}{7}(2z+\\frac{223}{49} \\ln|7z+22|)=x+c\\\\"
Answer
"\\frac{1}{7}(2(3y+2x)+\\frac{223}{49} \\ln|7(3y+2x)+22|)=x+c"
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