有數學唔識做？？

你係咪問緊

1. (1.5 x 6)x(-7x 1.5) / (1.5 x 6)
= -7 x 1.5
= -10.5
因為分子ge1.5 同 6 會同分母ge1.5 同 6 約簡, 所以會無左, 剩低-7 x 1.5

2. (-8 x -6 x -2) / (-4 x -3)
= 2 x 2 x -2
= -8
因為分子的-8同分母的-4約, 分子大d, -8/-4 ,所以除完剩低2
分子的-6同分母的-3約, 分子大d, -6/-3 ,所以除完都係剩低2

3. 6p+3-2p+5
= 6p -2p +3+5
=4p +8

4.12a-3b-11a-4b+7a
= 12a -11a +7a -3b-4b
= 8a-7b

*其實只係將同一種unknown or number 連埋個正負 放埋一齊, 分開黎計就可以

1.9 over 10.5
2.1over 8
3.4p+8
4.8a-7b

1.(-7)(1.5)分之(1.5)(6)
上下約左1.5
= -6/7


2.(-8)x(-6)x(-2)分之(-4)x(-3)
=12/48
=1/4

3.6p+3-2p+5
=4p+8

4.12a-3b-11a-4b+7a
=8a-7b

2007-07-02 00:14:48 補充：
sor..第2條睇少左x(-2)應該係2.(-8)x(-6)x(-2)分之(-4)x(-3)=12/(-96)=-1/8