▲急!6(x-2)+x(2-x)和(m-n)(x-y)-(n-m)(x+y)用提取公因式法怎么解?

题目

▲急!6(x-2)+x(2-x)和(m-n)(x-y)-(n-m)(x+y)用提取公因式法怎么解?
6(x-2)+x(2-x)和(m-n)(x-y)-(n-m)(x+y)用提取公因式法怎么解?
一步一步解出来.提取公因式法
提取公因式法!提取公因式法!
提取公因式法!提取公因式法!

答案

6(x-2)+x(2-x)
=6(x-2)+x[-(x-2)]
=6(x-2)-x(x-2)
=(x-2)(6-x)
(m-n)(x-y)-(n-m)(x+y)
=(m-n)(x-y)-[-(m-n)](x+y)
=(m-n)(x-y)+(m-n)(x+y)
=(m-n)[(x-y)+(x+y)]
=(m-n)[x-y+x+y]
=2x(m-n)