2-dimensional matrices
 

Alright, so tomorrow, I am going to a programming competition for high schoolers and they informed us that we should look up information about manipulate 2-dimensional matrices in various ways. I know about matrix that are used in Algebra 2, but I hardly remember ANY of it as well as I don't know if they are the same as used in a programming situation. So I am asking for help. Could you guys help let me know what kind of matrix they might be talking about. I am thinking they are talking about 2-D arrays (which creating and working with I know how to do). Could you guys give me some insight about, adding them, subtracting them, multiplying them, devising them, my teacher said something about inverses. Anything will help. And sorry to anyone if I should have posted this in a different way, or you think I'm a little kid.

OK, adding and subtracting matrices is easy - just add/subtract each element in the second matrix to the corresponding element in the first.

Finding the determinant is better explained by Wikipedia than by me - click.

To invert a square matrix, click. Essentially, you find the matrix of cofactors, transpose it (mirror it along the line from top-left to bottom-right), and divide the entire matrix by the determinant.

And finally, in order to multiply a matrix with either a scalar or a vector, you should check this out.