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Question
Find the value of x, if
\[\begin{vmatrix}3x & 7 \\ 2 & 4\end{vmatrix} = 10\] , find the value of x.
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Solution
\[\text{ Given }: \begin{vmatrix}3x & 7 \\ 2 & 4\end{vmatrix} = 10\]
\[ \Rightarrow 12x - 14 = 10\]
\[ \Rightarrow 12x = 24\]
\[ \Rightarrow x = 2\]
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