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If ∣6738∣=∣3x6−1x∣\begin{vmatrix}6 & 7\\ 3 & 8\end{vmatrix} = \begin{vmatrix}3x & 6\\ -1 & x\end{vmatrix}, then the sum of values of xx is equal

Solution

✅ Correct Option: 4

Left determinant =48−21=27= 48-21 = 27; right determinant =3x⋅x−6(−1)=3x2+6= 3x\cdot x-6(-1) = 3x^2+6.

So 3x2+6=27⇒x2=7⇒x=±73x^2+6 = 27 \Rightarrow x^2 = 7 \Rightarrow x = \pm\sqrt{7}.

The sum of the values is 0.

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