10(x+y)=400 100(x-y)=400这个二元方程组怎么解啊

X+Y=7(100X+Y)-(10Y+X)=(10Y+X)-(10X+Y) x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 化简 x / y(x+y) - y / x(x+y) = {x-y=100 {12%x-10%y=100 10X+Y+1/3Z=10Y+X 10X+Y+2/3Z=100X+Y x(x+y)(x-y)-y(y+x)(y-x)=(x-y)( )填空 200(x-y)=400 100(x+y)=400,求X和Y X+Y=10,X^3+Y^3=400,求X^2+Y^2 已知x+y=10,x^3+y^3=400,求x^2+y^2 x+y=20,x-y=10,y= y+10x=x+y+9 10y+x=y+10x+27 (x+y)/6+(x-y)/10=1,(x+y)/6-(x-y)/10=5 {6/x+y+10/x-y=30 6/x+y-10/x-y=-1 y+y+x=10,x+y+x=8,y=?,x=? 已知|x|+x+y=10 |y|+x-y=12 求 x+y=? 已知|x|+x+y=10,|y|+x-y=12,求x+y的值 已知|x|+x+y=10,x+|y|-y=12,求x、y的值 已知/x/+x+y=10,/y/+x-y=12.求x+y的值