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## Discriminant Edit

```  [a b
c d]
```

To solve for discriminant, do ad - bc

## Finding Inverse Edit

```  [a b
c d]
```

Switch the locations of a and d, and switch the signs of b and c. Your new matrix should be

```  [d -b
-c a]
```

Important!!: Don't forget the discriminant in front. That new matrix will be multipled by (1/[discriminant). Simply multiply each value by the fraction, and you will have an inverse matrix.

## Solving for x & y Edit

```[3 0   [x   =   [6
-3 1]   y]      -7]
```
• Find the inverse of matrix A using the previous explanation.
• Use this formula: A^-1 x C = B
• Multiply the inverse matrix with C to get a set of 2 values, which will be x on the top and y on the bottom.

## Decoding a matrix Edit

• You will need a 2x2 encoding matrix, which is given if you are decoding. You will have to make your own if you are encoding.
• Again, if decoding, you will be given a set of values. Enter them into a matrix with only 2 rows (otherwise it is impossible to multiply)
• Use A^-1 x C to get a new matrix. Each value will correspond to a letter in the alphabet, and you can use that to decode.
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