已知x^2-4xy+5y^2-6y+9=0,求((x+y+3)/(x-y+1))的值
已知x^2-4xy+5y^2-6y+9=0,求((x+y+3)/(x-y+1))的值
已知xy=2,x-y=3,求(x+y)(x-y)-y^2-(6x^2y-2xy^2)/2y的值.
已知xy=-2,x-y=3,求(x+y)(x-y)-y平方+(x-y)平方-(6x2y-2xy平方)/2y的值
初中数学分式已知x/y=2,求(x*x-xy+3y*y)/x*x+xy+6y*y的值
已知(x+2)*+|y+1|=0求5xy*-{2x*y-【3xy*-(4xy*-2x*y)】}的值
1.已知x+y=-4,xy=3,求5(2分之1xy+2y)+[6x-(2xy+y-3x)]的值
已知;x+y=4,x-y的绝对值=6,求xy(y的平方+y)-y的平方(xy+2x)-3xy
已知xy^2=-6,求-xy(x^3y^7-3x^2y^5-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*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
已知,x-y=5,xy=6,求(x+y)²-2x-2y+1的值
已知X+Y=6,XY=-4,求(5X-4Y-3XY)-(8X-Y+2XY)的值