a×42+720- 720 : 9 = 1060
a×42+720- 80 = 1060
a×42+720 = 1060+80
a×42+720 = 1140
a×42= 1140-720
a×42=420
a=420:42
a=10
100 -b : 16 +350 : 7 = 144
100 -b : 16 +50= 144
100 -b : 16= 144 -50
100 -b : 16=94
b : 16=100-94
b:16=6
b=6×16
b=96
E =100 ×a - 10 ×b
E =100 ×10 - 10 ×96
E=1000-960
E=40
Dacă tu crezi că merit, astept coroana!