九分之七乘负九分之八加九分之二乘负九分之八 简便计算

2025-12-13 21:07:06
推荐回答(1个)
回答1:

7/9×(-8/9)+2/9×(-8/9)
=(7/9+2/9)×(-8/9)
=1×(-8/9)
=-8/9