[a b c d]
To solve for discriminant, do ad - bc
[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 & yEdit
[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 matrixEdit
- 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.