5 个方程相加，再除以 4 ， 得x1+x2+x3+x4+x5 = 15/4该方程依次减去给定的 5 个方程，得x1 = 11/4, x2 = 7/4, x3 = 3/4, x4 = -1/4, x5 = -5/4
