Solving Affine Cipher with Number Theory

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SUMMARY

The discussion focuses on solving an Affine Cipher using number theory, specifically through modular arithmetic. The user initially sets up equations based on known character mappings, specifically C->A and B->T, leading to the equations 2a+b=0 (mod 26) and a+b=19 (mod 26). The user struggles with deriving the correct deciphering equation but ultimately resolves the issue, indicating a successful understanding of the Affine Cipher mechanics.

PREREQUISITES
  • Understanding of Affine Ciphers
  • Familiarity with modular arithmetic
  • Basic knowledge of number theory
  • Experience with solving linear equations in modular systems
NEXT STEPS
  • Study the principles of Affine Cipher decryption
  • Learn about modular arithmetic applications in cryptography
  • Explore advanced number theory concepts relevant to cryptographic algorithms
  • Practice solving various types of ciphers using number theory techniques
USEFUL FOR

Cryptography students, mathematicians interested in number theory, and anyone looking to deepen their understanding of cipher techniques and modular arithmetic.

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Homework Statement



Decipher the following text

KQEREJEBCPPCJCRKIEACUZBKRVPKRBCIBQCARBJCVFCUPKRIOF KPACUZQEPBKRXPEIIEABDKPBCPFCDCCAFIEABDKPBCPFEQPKAZ
BKRHAIBKAPCCIBURCCDKDCCJCIDFUIXPAFFERBICZDFKABICBB
ENEFCUPJCVKABPCYDCCDPKBCOCPERKIVKSCPICBRKIJPKABI


Homework Equations



I know that C->A and B->T

The Attempt at a Solution



that means my two equations are:

2a+b=0 (mod 26)
a+b=19 (mod 26)

I must be solving these wrong. I need to get a decipher equation and I keep getting

d(k)=15(y-5) (mod 26) but that doesn't allow K->O like it should.
 
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Nevermind, I figured it out.
 

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