a) (-23)×(-6)-(-72):(-6)-1032:8
+138-12-129= +126-129= -3
b) (-17)×(-8)-(-108):(-6)-1242:9
+136-18-138 = +112-138= -26
c) -121+17:[(93:3+3):2]×50=
-121+17:[(31+3):2]×50
-121+17:(34:2)×50
-121+17:17×50
-121+1×50
-121+50 = -71
d) -2×{2-3×[-6:3-9:(3:1-12)]}
-2×{2-3×[-6:3-9:(3-12)]}
-2×[2-3x(-6:3-9:(-9)]
-2×[2-3×(-2-1)]
-2×(2-3x-3)
-2×(2-9)
-2×(-11)
+22
