若2/3x-y=3/2x+y+5=5/4x+5y-1求x,y的值
若x-y/x+y=5,求x-y/2x+2y+5x+5y/3x-3y的值
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
若x^5+x^4y+x^4+x+y+1=0,且3x+2y=1,求x,y的值
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
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
(1)已知x+y=6,x²-y²=5,求x-y的值(2)若x+y=3,x²+y²
1.已知:x-2y=3,求[(3x+2y)(3x-2y)-(x+2y)(5x-2y)]除4x 的值
已知x-2y=2011,求[(3x+2y)(3x-2y)-(x+2y)(5x-2y)]÷4x的值.
若1/x-1/y=3,求5x+2xy-5y/x-4xy-y的值
若x、y、z满足2x+3y+z=18,4x-3y+5y=24,求x+3y的值.
已知x::y:z=3:4:5,(1)求x+y分之z的值;(2)若x+y+z=6,求x,y,z.
已知x^3+xy^2+x+x^2y+y^3+y=0,求5x-6y/3x+4y的值.