If \(\begin{vmatrix}-x & 12 \\-1 & 4 \end{vmatrix} = - 12\), find x.
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Correct Answer: Option D
Explanation:
\(\begin{vmatrix}-x & 12 \\-1 & 4\end{vmatrix} = - 12\)
-4x - (-1)12 = -12
-4x + 12 = -12
-4x = -12 - 12
-4x = - 24
x = 6
\(\begin{vmatrix}-x & 12 \\-1 & 4\end{vmatrix} = - 12\)
-4x - (-1)12 = -12
-4x + 12 = -12
-4x = -12 - 12
-4x = - 24
x = 6