# Decode the cryptogram was encoded from 2x2 matrix

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Nguyet Nguyen on 14 Aug 2022
Edited: KALYAN ACHARJYA on 14 Aug 2022
the cryptogram was encoded with 2x2 matrix What is the message?
5 2 25 11 -2 -7 -15 -15 32 14 -8 -13 38 19 -19 -19 37 16
I first tried to find the inverse of this code and then mutiply with the original one to get a decoded code, but it keeps saying invalid in the inverse command and I can't figure why, please suggest some solutions for me? ( uhm I do not ask for the rest of the code don't get me wrong)
This is my code
X =[5 2; 25 11; -2 -7; -15 -15; 32 14; -8 -13; 38 19; -19 -19; 37 16];
Y = inv(X);
C = mtimes(X,Y);
disp(C)

KALYAN ACHARJYA on 14 Aug 2022
Edited: KALYAN ACHARJYA on 14 Aug 2022
"but it keeps saying invalid in the inverse command and I can't figure why"
>> X =[5 2; 25 11; -2 -7; -15 -15; 32 14; -8 -13; 38 19; -19 -19; 37 16]
X =
5 2
25 11
-2 -7
-15 -15
32 14
-8 -13
38 19
-19 -19
37 16
Error:
Matrix Rule: Invertible matrices must be square, please see the reason it's why?