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If ∣ ∣ ∣ 3 X 7 − 2 4 ∣ ∣ ∣ = ∣ ∣ ∣ 8 7 6 4 ∣ ∣ ∣ , Find the Value of X. - Mathematics

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प्रश्न

If \[\begin{vmatrix}3x & 7 \\ - 2 & 4\end{vmatrix} = \begin{vmatrix}8 & 7 \\ 6 & 4\end{vmatrix}\] , find the value of x.

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उत्तर

\[\begin{vmatrix}3x & 7 \\ - 2 & 4\end{vmatrix} = \begin{vmatrix}8 & 7 \\ 6 & 4\end{vmatrix}\] 
\[ \Rightarrow 12x + 14 = 32 - 42\] 
\[ \Rightarrow 12x + 14 = - 10\] 
\[ \Rightarrow 12x = - 24\] 
\[ \Rightarrow x = - 2\] 
\[ \therefore x = - 2 .\]

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अध्याय 6: Determinants - Exercise 6.6 [पृष्ठ ९२]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 6 Determinants
Exercise 6.6 | Q 47 | पृष्ठ ९२

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