己知1/x-1/y=1 求(2x+6y+4x)/(x-y)
己知x平方+3xy一4y平方=0(y≠0)求代数式(1)y分之x(2)x+y分之x一y
已知4x=9y求(1)x+y/y (2)y-x/2x
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
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
己知|X-1/2|+|Y-9/2|=0,求代数式2X平方加Y的值.
1、x(x-y)(x+y)-x(x+y)^2
己知/x-4/+/y+2/=0,求2x-/y/的值.
己知(3X一2y+1)的平方与|4X一3y一3|互为相反数,求X,y的值?
若|x+2y-1|+y²+4y+4=0,求(2x-y)²-2(2x-y)(x+2y)+(x+2y)&
已知x²+y²+5=2x+4y,求代数式(2x²-(x+y)(x-y))x((x+y-1)
己知x,y, z都是非零有理数,且满足|x|/x+|y|/y+z/|z|=1,请你求xyz/|x