x dy + y dx=0 x dy=-y dx <- organizing equation dy/y = -dx/x <- dividing by x and y - separating equation Sdy/y=-Sdx/x <- integrate both sides ln|y| + c_{1}= -ln|x| + c_{2}<- fundamental theorem of Calculus ln|y|+ln|x| = C <- collecting constants e^(ln|y*x|)= e^C <- simplifying y*x=C_{2}<- simplifying further - new constant y=C_{2}/x