Раскройте скобки и упростите

1) 3a-(a+2b)= 3a-a-2b = 2a-2b = 2(a-b)

2) 5x-(2y-3x) = 5x-2y+3x = 8x-2y = 2(4x-y)

3) 3m-(5m-(2m-1)) = 3m-(5m-2m+1) = 3m-5m+2m-1 =  -1

4) 4a+(2a-(3a+3)) = 4a+(2a-3a-3) = 4a+2a-3a-3 = 3a-3 = 3(a-1)

Как-то так.