1. **State the problem:** Calculate the sum of two matrices: $$\begin{bmatrix}10 & 2 \\ 3 & 7\end{bmatrix} + \begin{bmatrix}-4 & 6 \\ 2 & 10\end{bmatrix}$$ 2. **Formula:** Matrix addition is done element-wise: $$\begin{bmatrix}a & b \\ c & d\end{bmatrix} + \begin{bmatrix}e & f \\ g & h\end{bmatrix} = \begin{bmatrix}a+e & b+f \\ c+g & d+h\end{bmatrix}$$ 3. **Calculate each element:** $$\begin{bmatrix}10 + (-4) & 2 + 6 \\ 3 + 2 & 7 + 10\end{bmatrix} = \begin{bmatrix}6 & 8 \\ 5 & 17\end{bmatrix}$$ 4. **Final answer for problem 1:** $$\boxed{\begin{bmatrix}6 & 8 \\ 5 & 17\end{bmatrix}}$$ --- 5. **State the problem:** Calculate the difference of two matrices: $$\begin{bmatrix}-7 & 8 \\ 9 & -6\end{bmatrix} - \begin{bmatrix}3 & -13 \\ 0 & -7\end{bmatrix}$$ 6. **Formula:** Matrix subtraction is done element-wise: $$\begin{bmatrix}a & b \\ c & d\end{bmatrix} - \begin{bmatrix}e & f \\ g & h\end{bmatrix} = \begin{bmatrix}a-e & b-f \\ c-g & d-h\end{bmatrix}$$ 7. **Calculate each element:** $$\begin{bmatrix}-7 - 3 & 8 - (-13) \\ 9 - 0 & -6 - (-7)\end{bmatrix} = \begin{bmatrix}-10 & 21 \\ 9 & 1\end{bmatrix}$$ 8. **Final answer for problem 2:** $$\boxed{\begin{bmatrix}-10 & 21 \\ 9 & 1\end{bmatrix}}$$