已知:4x = 5y,求(x+y) :y
已知:4x = 5y,求(x+y) :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=1/3,y=-1/2,求代数式x-(x+y)+(x+2y)-(x+3y)+(x+4y)-(x+5y)+...-(
已知x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
已知4x=9y求(1)x+y/y (2)y-x/2x
已知x^2+4y^2-4x+4y+5=0,求(y^4-x^4)/(y-2x)(x+y)*2x-y
已知X.x+y.y-4x+2y+5=0,求4X.X-12X Y+9Y.y的值
已知2x-y=10,求[(x²+y²)-(x-y)²+2y(x-y)]/4y
已知3X=4X,5Y=6Z求X+Y:Y+Z
已知y/x=2,则求代数式x+y/4x-5y的值
已知x²+y²-2x+4y+5=0,求x+y
已知x²+4x+y-2y+5=0求x+2y