已知:x-2y+3=0 求x^2-(4y+1)x+4y^2+2y
已知4x=9y求(1)x+y/y (2)y-x/2x
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x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
已知3x^2+xy-2y^2=0,求{(x+y)/(x-y)+4xy/(y^2-x^2)}/{(x+3y)*(x-y)}
已知4x-2y=0,求x-y/3x+2y的值
已知3x-4y/2x+y=1/2 求x/y的值
已知x,y>0 2x+y+3=xy 求5x+4y最小值
已知2x-y=10,求[(x²+y²)-(x-y)²+2y(x-y)]/4y
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x²+y²+5=2x+4y,求【2x²-(x-y)(x-y)】【(x+y-1)(x-y
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²