- #1

Firestrider

- 104

- 0

## Homework Statement

5) Determine the inverse of the matrix [tex]\begin{bmatrix}

6 & 17\\

13 & 21

\end{bmatrix}[/tex] mod 26

## Homework Equations

Solve for linear system of equations:

6a + 17c = 1 mod 26 6b + 17d = 0 mod 26

13a + 21c = 0 mod 26 13b + 21d = 1 mod 26

## The Attempt at a Solution

6 * (13a + 21c) = 6 * (0 mod 26)

- 13 * (6a + 17c) = 13 * (1 mod 26)

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78a + 126c = 0 mod 26

- (78a + 221c = 13 mod 26)

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95c = 13 mod 26

This is where I'm stuck. How do you divide 13 mod 26 by 95?