Ответ:
Пошаговое объяснение:
1)
2a +3a -8b = 5a -8b
-5b -8a+5b = -8a
6x+7-3x = 3x+7
-4x+18+18 = 36-4x
2) 5-2b -7-10b = -2 -5b
-3c-5x-9c+6x = x-12c
2a - 7y -5a+7y = -3a
11p+9c-12-11p-9c = -12
3) x-x+15+13+x = 28+x
3a-21 -2a -17+8a = 9a-38
2-4b -31b +6 -11 = -35b -3
14b-15b-y-y-10b = -11b-2y