We’ll start with an example:

company A’s total profit one quarter is;

first quarter: 100, second quarter 200, third quarter 300, and fourth quarter 400.

And company B’s total profit one quarter is;

first quarter: 400, second quarter 300, third quarter 200, and fourth quarter 100.

This you can write as: profit quarter: 1 2 3 4 company A 100 200 300 400 company B 400 300 200 100

Or just:

æ100 200 300 400ö

è400 300 200 100ø

Lets say that their profit change to the double the next quarter then we get the total profit for those two quarters is:

æ100 200 300 400ö æ200 400 600 800ö æ300 600 900 1200ö

è400 300 200 100ø + è800 600 400 200ø = è1200 900 600 300ø

This isn’t very hard it’s just to take the number in the number in the first row, first column, first matrix and use addition to add it to the first row, first column, second matrix. And then continue with the number in the first row, second column, first matrix and use addition to add it to the first row, second column, second matrix and so on. This also applies to subtraction with matrices.

(Note that you can only use subtraction and addition on matrices that has the same size)