已知x求^2+y^2-6x-8y+25=0求1/x-y /x+y/x^4-y^4
已知x.x+y.y+8x+6y+25=0,求代数式(x.x-4y.y)/(x.x+4xy+4y.y)-x/(x+2y)的
已知4x=9y求(1)x+y/y (2)y-x/2x
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
已知x的平方+y的平方-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)
已知x²+y²-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/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x^2+4y^2-4x+8y+8=0,求x+y
已知:x^2+y^2+4x-6y+13=0,求x^y值.
已知方程组4x+2y=1,20x+8y,求x,y
已知2x-y=10,求[(x²+y²)-(x-y)²+2y(x-y)]/4y
已知x^2+y^2-6x-8y+25=0,求分式y/x - x/y的值