化简:√(x^2+y^2+6x+9)+√(x^2+y^2-6x+9)=10..化晕了 貌似和椭圆有关系...

化简：x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y) xy²/(x²y-y) × x²/(x²+x)=(x²-3x)/(x²-5x) × 2x-10/(x²-6x+9)=化简求植x²-1/(x²-x-2)除以x/2x-4,其中x=1/2[x-x/(x+1)]除以[x/(2x-4)] ,其中x=√2+1 已知4x²+y²-4x-6y+10=0求（2/3x（√9x）+(y²√x/y³)×(x²√1/x×5x√y/x)的值 已知4x²+y²-4x-6y+10=0求（2/3x（√9x）+(y²√x/y³)-(x²√1/x-5x√y/x)的值 已知4x²+y²-4x-6y+10=0,求[(2/3)x√(9x)+y²√(x/y³)-(x²√(1/x)-5x√(y/x)的值 化简y(x+y)+(x+y)(x-y)-x^2 (x+y)^2+6(x+y)+9 计算:(2/3x√9x+6x√y/x)+(y√x/y-√1/x)帮忙啊~~~~~~~~~~~~~~~~~~~~~~~~~! 已知4x²+y²-4x-6y+10=0,求(2/3√9x+y²√x/y³)-(x√1/x-5x√y/x)的值. 已知4x²+y²-4x-6y+10=0,求(2/3√9x +y²√x/y³)-(x²√1/x -5x√y/x)的值. 已知实数x,y满足x=√(9-x+2y)+√(3x-6y-27)+5,则-2x-y的立方根为 若实数x,y满足x^2+6x+(√x-y+1) +9=0.求代数式(（1/x-y)+(1/x+y))除以y/x^2-y^2 的值（要求对代数式先化简,再求值） 已知4x²+y²-4x-6y+10=0,求（2x／3*√(9x)+y²√(x/y³))-(x²*√(1/x)-5x*√y/x))4x²+y²-4x-6y+10=0,4x²-4x+1+y²-6y+9=0(2x-1)²+(y-3)²=0x=1/2y=3这个我看不懂 【2(x-y)(x-y)(x-y)-8(x-y)(x-y)(x+y)+6y(x-y)(x-y)]/2(x-y)(x-y) 化简：(x+y)÷(√x-√y)-2xy÷(x√y-y√x)答得好有赏! 化简：{2/3x-2/(x+y)[(x+y)/3x-x-y]}/(x+y)/x 化简3x-2/(x+y)[(x+y)/3x-x-y]÷(x-y)/x √(x+2)+y+9=6√y 求x-y