Which property is shown in the matrix addition below?

In the given sum of matrices we need to add 0 to 0.

-5.5 to 5.5.

6 to -6

19.4 to -19.4

0 to 0 and

0 to 0.

We can see in the sums of -5.5 to 5.5, 6 to -6 and 19.4 to -19.4 we have equal numbers in opposite in signs.

Those are additive inverses of each other.

Therefore, we need to apply " Additive inverse property".