-11 (2x-3y)+12(3x+2y) = ?
9-(-8a+7b)-13 (-3a+4b) = ?
-0,7 (-5x+4b)+12(0,2b-0,5x) = ?

1) = -22x+33y+36x+24y = 14x+57y

2) = 72a+63b+39a-52b = 111a-11b

3)  = 3,5x-2,8b+2,4b-6x = -2,5x-0,4b