Solving Affine Cipher with Number Theory

[pupeye11]

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.

 

[pupeye11]

Nevermind, I figured it out.