Répondre :
a = 28 b + c = 15
b = 9
c = 6
ab = 28 X 9 = 252 ab = a X b
ac = 28 X 6 = 168 ac = a X c
ab + ac =
252 + 168 = 420
b = 9
c = 6
ab = 28 X 9 = 252 ab = a X b
ac = 28 X 6 = 168 ac = a X c
ab + ac =
252 + 168 = 420