求數學方程式的解，離開學生時期已久，想懇請大家幫忙?

取對數
    log 0.01525 = log A - n log 0.81 + m log 324000
    log 0.01275 = log A - n log 0.70 + m log 442800
    log 0.01o3o = log A - n log 0.66 + m log 478800
聯立解之. 也就是
    -1.816730156 = log A + 0.091514981 n + 5.51054501 m
    -1.894489815 = log A + 0.15490196 n + 5.646207612 m
    -1.987162775 = log A + 0.180456064 n + 5.680154142 m

解出
 log A  = -17.415209, A = 3.84409E-18

n = -7.553479
m = 2.956102