已知27^x=9,64^y=32,求x-y的值

已知27^x=9,64^y=32,求x-y的值 已知/x/+x+y=10,/y/+x-y=12.求x+y的值 已知|3x-y|+|x+y|=0,求x-y除以x*y的值. 已知x^2-y^2=27,x-y=3,求y/x的值 已知x-y=9,xy=5.求(x+y)(x+y)的值? 已知x^2-y^2=45 x+y=9,求X-y的值 已知2x-y/x+2y=3,求2(2x-y)/x+2y-9(x+2y)/2x-y+3的值. 已知X.x+y.y-4x+2y+5=0,求4X.X-12X Y+9Y.y的值 已知方程组{2x+y=6 x+2y=9},求x+y与x-y的值 已知(x+y)(x+y)=25,(x-y)(x-y)=9求xy与xx+yy的值 已知x+y=-5,x*x+y*y=19求xy和（x-y)*(x-y)的值 已知2/x+2/y=根号24,求 x/y(x-y) - y/x(x-y)的值