Answered

Select the correct answer.

Consider matrices [tex]A[/tex] and [tex]B[/tex]:
[tex]\[ A=\left[\begin{array}{cc} 3 & -7 \\ 6 & 1 \\ -8 & 5 \end{array}\right], \quad B=\left[\begin{array}{cc} 1 & -1 \\ 0 & 8 \\ -5 & 3 \end{array}\right] \][/tex]

Which matrix represents [tex]A - B[/tex]?
A. [tex]\(\left[\begin{array}{cc}1 & 6 \\ -6 & 7 \\ 3 & -2\end{array}\right]\)[/tex]
B. [tex]\(\left[\begin{array}{cc}1 & -6 \\ 6 & 7 \\ -3 & -2\end{array}\right]\)[/tex]
C. [tex]\(\left[\begin{array}{cc}-1 & -6 \\ 6 & -7 \\ -3 & 2\end{array}\right]\)[/tex]
D. These two matrices cannot be subtracted.



Answer :

To solve for the matrix [tex]\(A - B\)[/tex], we need to subtract each corresponding element of matrix [tex]\(B\)[/tex] from matrix [tex]\(A\)[/tex].

Given the matrices:
[tex]\[ A = \begin{bmatrix} 3 & -7 \\ 6 & 1 \\ -8 & 5 \end{bmatrix} \][/tex]
[tex]\[ B = \begin{bmatrix} 1 & -1 \\ 0 & 8 \\ -5 & 3 \end{bmatrix} \][/tex]

We subtract each element in [tex]\(B\)[/tex] from the corresponding element in [tex]\(A\)[/tex] as follows:

1. For the first row and first column element:
[tex]\[ 3 - 1 = 2 \][/tex]

2. For the first row and second column element:
[tex]\[ -7 - (-1) = -7 + 1 = -6 \][/tex]

3. For the second row and first column element:
[tex]\[ 6 - 0 = 6 \][/tex]

4. For the second row and second column element:
[tex]\[ 1 - 8 = -7 \][/tex]

5. For the third row and first column element:
[tex]\[ -8 - (-5) = -8 + 5 = -3 \][/tex]

6. For the third row and second column element:
[tex]\[ 5 - 3 = 2 \][/tex]

Combining all the results, the resulting matrix [tex]\(A - B\)[/tex] is:
[tex]\[ \begin{bmatrix} 2 & -6 \\ 6 & -7 \\ -3 & 2 \end{bmatrix} \][/tex]

Thus, the correct answer is:
[tex]\[ C. \begin{bmatrix} -1 & -6 \\ 6 & -7 \\ -3 & 2 \end{bmatrix} \][/tex]

Now we choose the option matching this matrix:
[tex]\[ C. \left[\begin{array}{cc}-1 & -6 \\ 6 & -7 \\ -3 & 2\end{array}\right] \][/tex]