2X/3-3Y/4=1/5 5X/6-5Y/2=2求X与Y值
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
已知x=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
已知4份之3x+2y=6份x-y+1=5份之2x+y,求x与y的值
(3x+2y)+(5x-y)i=17-2i.求x与y
已知|2-x|与|x-y+4|互为相反数,求代数式3(x-y)-5(x-y)-3(x-y)+(y-x)-4(x+y)+3
已知x^3+xy^2+x+x^2y+y^3+y=0,求5x-6y/3x+4y的值.
(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.
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
方程组:3y=x+4 ,2x+5y=-19 求x与y的值