7x^2-12xy+5y^2=0 怎样化成(7x-5y)(x-y)=0
若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y*
已知x,y>0 2x+y+3=xy 求5x+4y最小值
若x+y-5xy=0,求(2x-3xy+2y)/(x+2xy+y)的值
已知x²+y²-2x+4y+5=0,求X^4-y^4/2x^2+xy-y²·2x-y/xy
已知x-y=3xy,且xy不等于0,则-3x+6xy+3y/(7x-5y)-9xy-(3x-y)
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
已知7x^2+5y^2=12xy,并且xy不等于0,求x/y 和x-y的值
已知(x+2)^2+|x+y+5|=0,求3x^2y-[2x^2y-(2xy-x^2y)-4x^2]-xy
已知(x+2)^2+|x+y+5|=0,求3x^2y+{-2X^2y-[-2xy+(x^2y-4x^2)]-xy}
若(3xy+2)+|7-x-y|=0,求代数式(5xy+10y)-[-5x-(4xy-2y+3x)]的值.
已知实数x,y满足|x+y+7|+(xy-5)^2=0,求3x^2y^3+3x^3y^2
已知x2+y2-2x+4y+5=0,求(x^4-y^4)/(2x^2+xy-y^2)·[(2x-y)/(xy-y^2)]