點計??.....幫忙..

1. -4a+9a+5b-3b = 5a + 2b

2. 6x-7-(4x+5) = 6x-7- 4x-5 = 2x -12

3. 7x-6-2(3x-1) = 7x-6-6x+2 = x - 4

1. (-4a+9a) + (5b-3b) = 5a + 2b 2. 6x-7-4x-5 = (6x-4x) + (-7-5) =2x +(-12) =2x-12 <-- step1 要把 - 同括號ge+ 負負得正
3. 7x-6- (2 X 3x)-(2x-1) =7x-6-6x-2x-1 = -x-7 <--step1把2put in(3x-1)
38=]62801=--2007 負負得正

1. (-4a+9a) + (5b-3b) = 5a + 2b <--同類項(姐係同一個變數/英文字母) 相加/相減
2. 6x-7-4x-5 = (6x-4x) + (-7-5) =2x +(-12) =2x-12 <-- step1 要把 - 同括號ge+ 負負得正
3. 7x-6- (2 X 3x)-(2x-1) =7x-6-6x-2x-1 = -x-7 <--step1把2put in(3x-1)

2007-08-03 17:28:22 補充：
Q3 計錯 係7x-6- (2 X 3x)-(2 X -1) = 7x-6-6x 2 = x-4 <--step1把2put in(3x-1)

我吾知答案arr. = =

我都仲未學到,sorry.

2007-08-03 17:29:29 補充：
你地識個d,可吾可以教我arr, please.

answer:

1.5a+2b

2.2x-13

3.x-4

1. 5a+2b

2. 2(x-6)

3. x-4


唔知o岩唔o岩~~小心~

1. -4a+9a+5b-3b=5a+2b 2. 6x-7-(4x+5)=6x-7-4x-5=2x-12
3. 7x-6-2(3x-1)=7x-6-6x+2=x-4 Hope i can help you1