已知|x-2|+|2x-3y+8 |=0求x的y次方y平方-y的x次方*x平方的值

已知X*X+Y*Y+6X-8Y+25=0 求（Y/X)+(X/Y)-2=? 已知|x+y-3|+(x-y)2=0则 已知x-3y=0,求(2x+y)/(x^2-2xy+y^2)X(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x-y/x+y=y+z/2(y-z)=z+x/3(z-x),求证8x+9y+5z=0THX.. 已知x^2+y^2-8x+12y+52=0 ,求1/2x-1/x-y(x-y/2x-x^2+y^2) 已知x^2+y^2-8x+12y+52=0 ,求1/2x-1/x-y(x-y/2x-x^2+y^2) 已知实数x.y满足根号(x+y-8)+根号(8-x-y)=根号(3x-y-4)+根号(x-2y+7),求x,y 已知x^2+4y^2-4x+8y+8=0,求x+y 已知3x-4y=0,则x^2-y^2/x^2+y^2 已知x^2-3xy+2y^2=0 则x/y+x/y= 已知x-y=3,x+y=8,问x^2 -y^2=? 已知2x-3y=0则3x-y比x+2y= 已知x+y=0,求x^3+x^2*y+xy^2+y^3 已知x>0,Y>0,如何证x^2/y+y^2/x>=x+y 已知(x+y)(x+y-2)-8=0,求x+y的值 已知|5x-y-8|+(7y-x+2)=0则4x+6y 已知（x+y）×（x+y+2）-8=0,求x+y的值