（4xˇm yˇn‐8xˇn yˇm）‐（‐5xˇn yˇm‐3xˇm yˇn﹚

(x+y)(m+n)2-(x+y)(m+n)2 (m+n)(x-y)-(m+n)(x+y)的答案 (m+n)(x-y)+(m-n)(y-x) (m+n)(x-y)-(m+n)(x+y)的结果 m(x-y)+n(y-x) 把下列各式因式分解(2m+3n)(2m-n)-4n(2m-n)(x+y)^2(x-y)+(x+y)(y-x)^24a(x 计算（1）（3m-4n)(3m+4n)-(2m-2n)(2m+n) (2)(x+5y)²-(x-5y) a(x-y)-b(y-x)+c(x-y) x(m+n)-y(n+m)+(m+n) 急数学题x,y,m,n满足条件x/y=y/n=m/n=5/8,求x+y+m+n的最小值? 3x+4y=-5 5x+6y=-9 (n-8m)x-8y=10 5x+(10m+2n)y=-9 求m.m+n.n=? 因式分解m²+2m(m-n)+(m-n)²,16-8（x-y）+（x-y）² (x+y)(5m+3m)的平方-（x+y)(m-n)的平方 因式分解