以知x-y=-3,-x+3y=2,求x的平方-4xy+3y的平方的值

以知x,y满足1/2[x-y]+[1-y]=0,求7x-3y的值 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 y=3(x-y),x=2(x-y)求x,y的值 以知X+Y=4,X*2+Y*2=10,求X*3+Y*3,X*4+Y*4的值 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 以知:x^3-3y^2=2xy,求x+2y/x-y=? 以知x,y满足1/2[x-y]+[1-y]=0,求7x-3y的值[]为绝对值 已知x-y=1,求[(x+2y)^2+(2x+y)(x-4y)-3(x+y)(x-y)]除以y的值大神们帮帮忙 已知x-y=1,求[(x+2y)²+(2x+y)(x-4y)-3(x+y)(x-y)]÷y的值 已知(x+2y)(2x-3y)=y(y-4x),试求x/y的值 已知3x =2y 求x/x+y+y/x-y-y²/x²-y² 已知|3x-y|+|x+y|=0,求x-y除以x*y的值. y=x/3+2/x,求y的最小值 y=/x+2/+/x-3/求y的最小值 x/3=y/4,求(x*x-xy)/(x*x+y*y)的值 已知:3x-5y=0,求x/y,x-y/y,x-y/x 已知（x+y）2 =2,(x-y)3 =3,求(x+y)7(x-y)2(x+y)3(y-x)4 的值