中一數學題!!!急!聽日考試 我出20點

第一題 :
2(3m-1)-3(m+2)=1
6m-2-3m-6=1
3m-8=1
3m=9
m=3

第二題:
5mn^2+4m^2n-(2mn+6m^2n-mn^2)+(2m^2n-8mn^2)
=5mn^2+4m^2n-2mn-6m^2n+mn^2+2m^2n-8mn^2
=-2mn^2-2mn

1.2(3m-1)-3(m+2)=1
6m-2-3m-6=1
3m-8=1
3m=9
m=3
2.I can't find

2.
5mn to the power 2+4m to the power 2n-(2mn+6m to the power 2n-mn to the power 2)+(2m to the power 2n-8mn to the power 2)

= 5mn to the power 2+4m to the power 2n-2mn-6m to the power 2n+mn to the power 2+2m to the power 2n-8mn to the power 2

=5mn to the power 2+mn to the power 2-8mn to the power 2+4m to the power 2n-6m to the power 2n+2m to the power 2n-2mn

=(5+1-8)mn to the power2+(4-6+2)m to the power 2n-2mn

= -2mn to the power 2-2mn

2(3-1)-3(m+2)=1
6-2-3m+6=1 (加減運算)
10-3m =1
9=3m (一齊除3)
m=3

第二題都打吾到個2次
sorry

2(3-1)-3(m+2)=1
6-2-3m-6=1
-2-3m=1
3m=1+2
m=1

mn2=a m2n=b mn=c
5a+4b-(2c+6b-1a)+(2b-8a)
5a+4b-2c-6b+1a+2b-8a
=-2a-2c

唔明再問

2008-01-04 19:37:29 補充：
第1.. 果度係-3m=3m=-1 ..sorry~^^

2008-01-05 05:19:28 補充：
2(3m-1)-3(m 2)=1 6m-2-3m-2=13m-4=13m=1 4m=3/5

1.2(3-1)-3(m+2)=1
2(2)-3m-6=1
-3m=1+6-4
-3m=3
m=-3

sorry , I cannot find the no.2 question

2008-01-04 19:35:54 補充：
m=-1一時手快, 打錯!!!!!!!

2008-01-05 12:54:20 補充：
1.2(3m-1)-3(m+2)=1 6m-2-3m-6=13m=1+2+43m=9m=3

1]
2(3-1)-3(m+2)=1
6-2-3m-6=1
-2-3m=1
-3=3m
m=-1
2]
你比msn我,我答你,因為我唔識系到講,唔識打~