若√x-4y=4,(3x+5y)^3=-27,求(x+y)^2n的值（n为整数）

（5x+3y)(3y-5x)-(4x-y)(4y+x)= 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 先化简再求值(x-y)(x-2y)+(x-2y)(x-3y)-2(x-3y)(x-4y) x=4 y=5 (x-y) (x-2y)+(x+2y) (x-3y)-2(x-3y) (x-4y)= 先化简 再求值 (2x-y)(y+x)-(x-2y)(2y+x)-(-3y+x)^2其(√x+1)+y^2+4=-4y 化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1 若5x+3y=3x+4y=x+2y+6,则x+y=___ 若x/y=4/3 则3x+2y/2x-5y= 若2x-3y=0,求5x+4y/3x-2y (4x-2y-z)-{5x[8y-2y-(x+y)]-x+(3y-10z)]=? kuaihuajian 3X=5Y （X+Y)*3X=(2Y+X)*4+2*2 若(-x+6):(x-y):(4x+y)=3:14:1,求x+y 若(-x+6):(x-y):(4x+y)=3:14:1,求x+y 比例线段若x+y/x-y=4/3,则x/y=x+y/x-y=4/3,则x/y=要快~~ 若2x-3y+4=0则x（x*x-1)+x(5-x*x)-6y+7 若x+y=4,则多项式1/2(x+y)+4(x-y)-3（x-y）-3/2(x+y)-x+y值是（）