Question

[HoangJVan]

 Tính hợp lí:

1. 73.(8-59)-59.(8-73)
2. 159.(18-59)-59.(18-159)
3. -145.(13-57)+57.(10-145)
4. 17.(15-16)+16.(17-20)
5. -38.(25-4)+35.(-4+38)
6. 23.(145-17)-145.(23-6)
7. 199.(15-17)-199.(-17+5)
8. -39.(5-99)+99.(10-39)

Answer 1

[Đoàn Việt Hoàng]

1.73.(8-59)-59.(8-73)

=73.8-73.59-59.8-59.73

=73.(59-59)-8.(73-59)

=73.0-8.14

=0-112

=-112

2.159.(18-59)-59.(18 - 159)

=159.18-59.159-59.18-59.159

=159.(59-59)-18.(159-59)

=159.0-18.100

=0-1800

=-1800