已知x+y+y=20,x+y=15求x.y
已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y
已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y)
已知:4x = 5y,求(x+y) :y
已知/x/+x+y=10,/y/+x-y=12.求x+y的值
已知4x=9y求(1)x+y/y (2)y-x/2x
已知|3x-y|+|x+y|=0,求x-y除以x*y的值.
已知2x-y=10,求[(x²+y²)-(x-y)²+2y(x-y)]/4y
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
已知2/x 2/y=根号24,求 x/y(x-y) - y/x(x-y)的值
已知x/y=2,求2x(x+y)-y(x+y)/4x²-4xy+y²
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?