Odpowiedzi

2010-01-18T16:26:49+01:00
1. 6a+12b-3a+9b=3a+21b
2. 7b+7c-3b-6c=4b-c
3. 4b+12+3a-3b=b+12+3a
4. 5a+15+2b-3a-3b=2a+15-b

Liczę na najlepszą! ;)
2010-01-18T16:28:12+01:00
6(a+2b)-3(2a-3b)= 6a+12b-6a+9b=21b
7(b+c)-3(b+2c)= 7b+7c-3b-6c=4b+c
4(b+3)+3(a-b)= 4b+12+3a-3b=7b+12+3a
5(a+3)+2b-3(a+b)=5a+15+2b-3a-3b=2a-b+15
2010-01-18T19:49:42+01:00
6(a+2b)-3(2a-3b)= 6a+12b-6a+9b=21b
7(b+c)-3(b+2c)= 7b+7c-3b-6c=4b+c
4(b+3)+3(a-b)= 4b+12+3a-3b=7b+12+3a
5(a+3)+2b-3(a+b)=5a+15+2b-3a-3b=2a-b+15

^^