1.2x+3y-2=0 4x-9y+1=0 2.2x+y=2 3x-2y=10

{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 1.2x+3y-2=0 4x-9y+1=0 2.2x+y=2 3x-2y=10 已知X,Y,满足(X+3Y)(X-3Y)=-10(Y^2-6/5)和2X(Y-1)+4(1/2X-1)=0 9y=3x-(x-1),4(x+y)-(2x+4)=8y 已知3x^2+xy-2y^2=0,求{(x+y)/(x-y)+4xy/(y^2-x^2)}/{(x+3y)*(x-y)} 先化简再求值(x-y)(x+y)-(x-2y) 的完全平方+x(3x-5y)-(x-y)(x-2y),其中x=1/2 y 化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1 已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) 已知x,y满足{3x-y=9 {x-3y=0 求x+2y+ 4y的平方/x-2y -4x的平方y/x的平方-4y的平方 已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-( {4x-3y-10=0 3x-2y=0,{3x-4(x-y)=2 2x-3y=1,{2(x+y)-(x-y)=3 (x+