5 Linear Cipher (6 pts)
Qyodcxan Squatqa us ty oyna glycx qyodcxans xpgt gsxnytyow us glycx xajasqydas. Avskan M. Vuzesxng.
Assume that the ciphertext us represents the plaintext word is. Also, assume
that it was encrypted using a linear cipher. The numbering of the characters is
A=1, B=2, · · ·, Y = 25, Z = 0.
Find the encryption function
y = ax + b mod 26
which takes a plaintext letter as input and outputs the matching ciphertext
letter y.
6 Decipher (6 pts)
Using the information from the previous problem, solve for x in terms of y. Use
this to help decrypt the message at the beginning of question 5.
