First off, "answer to this matrix" doesn't make any sense. A matrix isn't a problem, it's an object, like a number or expression.
You're asked to compute the difference between two matrices. When you're given two matrices of same dimension (same number of rows and columns), the sum/difference of them is the matrix whose components are sums/differences of the corresponding components.
As a simple example,

In this case,
![\begin{bmatrix}-4&-5&5\\1&6&3\\-2&2&1\end{bmatrix}-\begin{bmatrix}-6&-1&-6\\6&-3&-2\\4&-1&-3\end{bmatrix}=\begin{bmatrix}-4-(-6)&-5-(-1)&5-(-6)\\1-6&6-(-3)&3-(-2)\\-2-4&2-(-1)&1-(-3)\end{bmatrix}]()
