Value(s) of \(x\) for which, \(\begin{vmatrix}x & 1\\ 5 & x\end{vmatrix}=\begin{vmatrix}8 & 2\\ 2 & 1\end{vmatrix}\) is:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → \(\pm 3\)
Expanding both determinants:
\(x \cdot x - 1 \cdot 5 = 8 \cdot 1 - 2 \cdot 2\)
\(x^2 - 5 = 4\)
\(x^2 = 9\)
\(x = \pm 3\)