Odpowiedzi

2009-04-06T20:20:30+02:00
2a - 5b + (7-3a-2b) = 2a - 5b + 7 - 3a - 2b = -a - 9b +7 = 7 - (a + 2b)
2009-04-06T20:20:42+02:00
2a - 5b + (7-3a-2b) =2a-5b+7-3a-2b=-a-7b+7
2009-04-06T20:21:18+02:00
2009-04-06T20:21:52+02:00