In arithmetic, the aditive identity says that for some number a, a + 0 = 0 + a = 0. what would be an aditive
identity in matrix arithmetic?

Let's have a matrix [M]

The aditive identity for matrix arithmetic would be [M]+[0]=[0]+[M]

Step-by-step explanation:

Let [0] be a full-zero matrix

If we add [0] for any [M] matrix, the [M] matrix won't change.

Then [M]+[0]=[0]+[M]=[M]

a) what number, when added to negative four, is equal to negative five?

step-by-step explanation:

i think this could be a possible answer (1 / 84) -1

good luck! : d