After the 5 crypto start-ups, its time to get harder. For my next 3 problems, there will be a semi-fixed decipher method. And, it will be like this.
Lets say the cipher is '\(ax^2+bx+c\)'.
In order to decode 'a', I may use 1001 or 277-2. The first number is 'a', second is 'b', and so on. The last number is 'x'.
i.e. 1 x 1^2=1 and 2 x (-2^2) +7 x (-2) +7=1
If there are desperate needs, the answer may also be 27, 53, etc... Just mod26.
But the cipher may not be '\(ax^2+bx+c\)'. The first one is, but from then on, its on your own. I will only put 1 digit, positive or negative, so that it will not be that misleading.