已知2x-y=18
已知2x-y=18
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y=根号(x-8)+根号(8-x)+18,求代数式[(x+y)/(根号x+根号y)]-2xy/(x根号y-y根号x)
已知y=√(x-8)+√(8-x)+18,求代数式 (x+y)/(√x-√y)-2xy/(x√x-y√x) 的值
数学题已知p=x^/x-y-y^/x-y,q=(x+y)^-2Y(X+Y),
已知4x=9y求(1)x+y/y (2)y-x/2x
已知2y-3x+3=0 求(2y-3x)^3x-2y+3(3x-2y)-18÷(2y-3x)
已知当x=8,y=18,求(x+y)/(根号x-根号y)-(2xy)/(x根号y-y根号x)
已知2x-y=10,求[(x²+y²)-(x-y)²+2y(x-y)]/4y
已知x*x+4x+y*y-2y+5=0,则x*x+y*y=?
已知2/x+2/y=根号24,求 x/y(x-y) - y/x(x-y)的值