已知(x 5y-8)^2 (2x 4)=0,且5x-ky=0,求k的值.kkkkkkkkkkkkkkkkkkkk!sorry!已知(x+5y-8)^2+(2x+4)=0,且5x-ky=0,求k的值.

已知|5x-y-8|+(7y-x+2)=0则4x+6y 已知x*x+4x+y*y-2y+5=0,则x*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^2+4y^2-2x-2x+8y+5=0,求x^2-y^2/2x^2+xy-y^2*2y-y/xy-y/(x^2+y^2/y)^2的值 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.x+y.y-4x+2y+5=0,求4X.X-12X Y+9Y.y的值 已知x^2+4y^2-4x+8y+8=0,求x+y 已知x^2+y^2-4x+2y+5=0则x^y=? 已知x^2+4x+y^2+2y+5=0,则x^y= 已知x-y+2>=0,x+y-4>=4,2x-y-5 已知4x^2+y^2-4x+4y+5=0,求x,y 已知x-2y=2,求4x-y-8分之3x+y-6 已知{x-y+2>=0,x+y-4>=0,2x-y-5 已知x²+4x+y-2y+5=0求x+2y 已知4x=5y,那么(3x+y)/(x-2y)= 已知x²+4x+y²-2y+5=0,则x+y= 已知x平方+y平方-2x+4y=-5,求x,y 已知x的平方+y的平方-2x+4y=-5,求x、y