x²+xy=2和y(x+y)=3
x(x+y)=2①
y(x+y)=3②
①÷②得x/y=2/3
x=2/3y
代入②得
5/3y²=3
y²=9/5
即y1=3√5/5;
x1=2√5/5
y2=-3√5/5;
x1=-2√5/5