问题 解答题
化简:
(-144)×(-169)

②-
1
3
225

18m2n

2
3
3
3
4
×(-9
45
)
答案

(-144)×(-169)
=
144×169
=12×13=156;

②-

1
3
225
=-
1
3
×15=-5;

18m2n
=3|m|
2n

2
3
3
3
4
×(-9
45
),

=

2
3
×(-9)×
15
4
×45

=(-6)×

15
3
2

=-45

3

名词解释
问答题