Ａ＋Ｂ＝９１ Ｂ＋Ｃ＝６３ Ａ＋C＝４6求ABC是多少
Ａ＋Ｂ＝９１ Ｂ＋Ｃ＝６３ Ａ＋C＝４6求ABC是多少
日期：2013-07-29 15:29:29 人气：2
A + B = 91 (1)
B + C = 63 (2)
A + C = 46 (3)
(1) + (2) + (3)
==> 2(A+B+C) = 91 + 63 + 46
==> A + B + C = 100 (4)
(4) - (1) ==> C = 100 - 91 = 9
(4) - (2) ==> A = 100 - 63 = 37
(4) - (3) ==>