-21, 6 : (-0, 12) + 9, 6 : (8, 9 - 11, 3) = 176.
1) -21, 6 : (-0, 12) = 180.
2) 8, 9 - 11, 3 = -2, 4.
3) 9, 6 : (-2, 4) = -4.
4) 180 + (-4) = 176.
-21, 6 : (-0, 12) + 9, 6 : (8, 9 - 11, 3) = 176.
1) -21, 6 : (-0, 12) = 180.
2) 8, 9 - 11, 3 = -2, 4.
3) 9, 6 : (-2, 4) = -4.
4) 180 + (-4) = 176.