X+Y=5,x-y=8,求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.y-6x-8y+25=0,求3x.x+5y的值
二元函数f(x,y)=x+y/x-y,求f(y/x,x/y)
求y'=y/(y-x)
|x|=3 |y|=5 |x-y|=|x|+|y| 求 X+Y和 X-Y 等于多少
已知x+y=-5,x*x+y*y=19求xy和(x-y)*(x-y)的值
求x:y:z x:y=7/5:7/3,y:x=7:8
已知X-Y/X+Y=3,求代数式2(x-y)/X+Y-3X+Y/X+Y
已知x-2y=2016,求[(3x+2y)(3x-2y)-(x+2y)(5x-2y)]除以8x的值
已知x-2y=2012,求[(3x+2y)(3x-2y)-(x+2y)(5x-2y)]/(8x))
已知x-2y=2012,求[(3x+2y)(3x-2y)-(x+2y)(5x-2y)]÷8x的值