123_N = 93_(N+2)
1*N^2 +2*N^1 +3*N^0 = 9*(N+2)^1 + 3*(N+2)^0
N^2 +2N +3 = 9N+18 +3
N^2 +2N -9N -18 = 0
N^2 -7N -18 = 0
D = 49 +18*4 = 121
N = (7-11)/2 = -2
N = (7+11)/2 = 9
ответ: 9.
123_N = 93_(N+2)
1*N^2 +2*N^1 +3*N^0 = 9*(N+2)^1 + 3*(N+2)^0
N^2 +2N +3 = 9N+18 +3
N^2 +2N -9N -18 = 0
N^2 -7N -18 = 0
D = 49 +18*4 = 121
N = (7-11)/2 = -2
N = (7+11)/2 = 9
ответ: 9.