1. **State the problem:** We need to find the matrix $A$ given by the equation:
$$A = 3.1 \begin{bmatrix} 1 & -4 & 0 \\ -2 & 2 & -1 \end{bmatrix} - 1.2 \begin{bmatrix} -1 & 2 & 5 \\ -2 & 0 & -3 \end{bmatrix}$$
and determine which of the given options matches the result.
2. **Recall the matrix scalar multiplication and subtraction rules:**
- Multiply each element of a matrix by the scalar.
- Subtract corresponding elements of the two matrices.
3. **Calculate each scalar multiplication:**
$$3.1 \times \begin{bmatrix} 1 & -4 & 0 \\ -2 & 2 & -1 \end{bmatrix} = \begin{bmatrix} 3.1 & -12.4 & 0 \\ -6.2 & 6.2 & -3.1 \end{bmatrix}$$
$$1.2 \times \begin{bmatrix} -1 & 2 & 5 \\ -2 & 0 & -3 \end{bmatrix} = \begin{bmatrix} -1.2 & 2.4 & 6 \\ -2.4 & 0 & -3.6 \end{bmatrix}$$
4. **Perform the subtraction:**
$$A = \begin{bmatrix} 3.1 & -12.4 & 0 \\ -6.2 & 6.2 & -3.1 \end{bmatrix} - \begin{bmatrix} -1.2 & 2.4 & 6 \\ -2.4 & 0 & -3.6 \end{bmatrix} = \begin{bmatrix} 3.1 - (-1.2) & -12.4 - 2.4 & 0 - 6 \\ -6.2 - (-2.4) & 6.2 - 0 & -3.1 - (-3.6) \end{bmatrix}$$
5. **Simplify each element:**
$$A = \begin{bmatrix} 3.1 + 1.2 & -12.4 - 2.4 & 0 - 6 \\ -6.2 + 2.4 & 6.2 & -3.1 + 3.6 \end{bmatrix} = \begin{bmatrix} 4.3 & -14.8 & -6 \\ -3.8 & 6.2 & 0.5 \end{bmatrix}$$
6. **Compare with the options:** The matrix matches the second option:
$$\begin{bmatrix} 4.3 & -14.8 & -6 \\ -3.8 & 6.2 & 0.5 \end{bmatrix}$$
**Final answer:**
$$A = \begin{bmatrix} 4.3 & -14.8 & -6 \\ -3.8 & 6.2 & 0.5 \end{bmatrix}$$
Matrix Solution 578B5E
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