已知-4x+3y-13+(y-3)^2=0,则x·y=

已知x,y满足x²+y²-4x+6y+13=0则(3x+y)²-(3x+y)(3x-y)的 已知x,y为实数,根号3x+4 +y^2-6Y+9=0则x+y=? 已知3x^2+xy-2y^2=0,求{(x+y)/(x-y)+4xy/(y^2-x^2)}/{(x+3y)*(x-y)} 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x-2y/2x+3y=3/4,则x：y= 已知4x-2y=0,求x-y/3x+2y的值 已知x,y>0 2x+y+3=xy 求5x+4y最小值 已知x*x+y*y-4x-6y+13=0,求3x+4y的值 已知x-y-3绝对值+(2x+2y+10)的平方=0,则(x+y)(x-Y)= 已知x,y满足:x平方+y平方-4x+6y+13=0求(3x+y)-3（3x-y)(x+y)-(x-3y)(x+3y)=