Given y(x+y)=3 evaluate dy/dx when y=1

y(x+y)=3,yx +y² =3,Differentiating with respect to x,y+x(dy/dx) +2y(dy/dx)=0when y=1, x=3-1=2 (from original equation)1+2(dy/dx) +2(dy/dx)=0,dy/dx=-1/4