Subtract the matrices. What number fills in ?

The missing number for the subtraction of matrices is 4.
The subtraction of two matrices of the same size is really direct. You just need to subtract the elements that are in the same position, then:
[tex]A = \left[\begin{array}{ccc}a_{11}&a_{12}\\a_{21}&a_{22}\end{array}\right] \\\\B = \left[\begin{array}{ccc}b_{11}&b_{12}\\b_{21}&b_{22}\end{array}\right]\\\\A - B = \left[\begin{array}{ccc}a_{11} - b_{11}&a_{12}-b_{12}\\a_{21} - b_{21}&a_{22}-b_{22}\end{array}\right][/tex]
Then the missing therm will just be equal to the difference between the last two elements of each matrix:
-2 - (-6) = -2 + 6 = 4
The missing number is 4.
If you want to learn more about matrices:
https://brainly.com/question/11989522
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