(x^2+y^2)(x^2+y^2+5)-36=0
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)
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*
先化简再求值(x-y)(x+y)-(x-2y) 的完全平方+x(3x-5y)-(x-y)(x-2y),其中x=1/2 y
已知x^2+4y^2-4x+4y+5=0,求(y^4-x^4)/(y-2x)(x+y)*2x-y
.先化简再求值:(2x+y)(2x+y)-(2x-y)平方其中X,Y满足X平方+Y平方-2X+4Y+5=0
若3x-5y=0,则x+y/x=(),x-y/y=(),2x-3y/2x+3y=( )
已知X.x+y.y-4x+2y+5=0,求4X.X-12X Y+9Y.y的值
解方程组(x+y)(x-2y)=-5 (x-y)(x+2y)=7
设Z=X+Y,其中X,Y满足X+2Y>=0,X-Y
6(x-y)-2(x+y)=14 3(x-y)+(x+y)=5
3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27