1/3x+3/4y=5/12 2/3x-5/6y=-1/3 x和y各是多少?
已知X,Y,满足(X+3Y)(X-3Y)=-10(Y^2-6/5)和2X(Y-1)+4(1/2X-1)=0
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=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
3x+2y/4=2x+y/5=x-y+1/6
解方程组3(x+y)-4(x-y)=4和(x+y)/2+(x-y)/6=1
若2x-3y+4=0则x(x*x-1)+x(5-x*x)-6y+7
已知4x+y=5和3x+2y=4,则x-y的值是多少
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
(x+2)(x+3) (x-4)(x+1) (y+4)(y-2) (y-5)(y-3)
{4/(x+y)+6/(x-y)=3 {9/(x-y)-1/(x+y)=1