x^2-9y^2-x-3y... 做错的 帮下

x^2-9y^2-x-3y... 做错的 帮下 5x=3y,(2x+y)的平方=5x(x+y)+9 已知2x-y/x+2y=3,求2(2x-y)/x+2y-9(x+2y)/2x-y+3的值. 9xy(x-y)(x+1)-3y(x-y)(3x+2y)+6y的平方(x-y)(x+1),因式分解 已知x-y=3,求[（x+y)(x-y)-(x-y)^2+2y(x-y)]除以的值 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 [(x+2y)(x-2y)-(2x-y)²+(3x-y(2x-5y)]/(-x)的解答 (x+3y)的平方+2(x-y)(x+y)+(x-3y)的平方 2(y-x)的平方-7(x-y)+6(x-y)-3(y-x)的平方 请帮我看看我那里做错了!y=[x^2*(三次根号下x^2)]/根号下x^5=x^(8/3)/x^(5/2) y=3(x-y),x=2(x-y)求x,y的值 x(x-y)2-(y-x)3 化简：{2/3x-2/(x+y)[(x+y)/3x-x-y]}/【(x-y)/x】的负二次方 (x+3y)(x-3y)(x的2次方-9y的2次方） 已知：x+9y=y-3x,求(x^2-y^2)/(x^2+y^2)的值RT 3(x+y)-2(x-y)=11 4(x+y)+3(x-y)=9 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 81/8*(-x-y)^6*(x-y)^3*4/9(x+y)^4*(y-x)^2