[x+2y=0 3x+4y=6

{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20 {(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20 4(x+y)-3(x-y)=-20,2/x+y+3/x-y=6 若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 【2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2】/2(x-y)^2= y-3x=2,y-5x=4,y-7x=6,y-9x=8,y-11x=0方程组, 已知X,Y,满足(X+3Y)(X-3Y)=-10(Y^2-6/5)和2X(Y-1)+4(1/2X-1)=0 已知x^3+xy^2+x+x^2y+y^3+y=0,求5x-6y/3x+4y的值. 已知3x^2+xy-2y^2=0,求{(x+y)/(x-y)+4xy/(y^2-x^2)}/{(x+3y)*(x-y)} 已知x,y满足x²+y²-4x+6y+13=0则(3x+y)²-(3x+y)(3x-y)的 如果分式3x-6y/x+y=0,那么x,y 应满足 A、x=2y B、x≠-y C、x=2y且x≠-y D、x=2y且y