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Find the Value of X, If ∣ ∣ ∣ 2 3 4 5 ∣ ∣ ∣ = ∣ ∣ ∣ X 3 2 X 5 ∣ ∣ ∣

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Question

Find the value of x, if

\[\begin{vmatrix}2 & 3 \\ 4 & 5\end{vmatrix} = \begin{vmatrix}x & 3 \\ 2x & 5\end{vmatrix}\]

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Solution

\[\text{ Given }: \begin{vmatrix}2 & 3 \\ 4 & 5\end{vmatrix} = \begin{vmatrix}x & 3 \\ 2x & 5\end{vmatrix}\]
\[ \Rightarrow 10 - 12 = 5x - 6x\]
\[ \Rightarrow - 2 = - x\]
\[ \Rightarrow x = 2\]

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Chapter 5: Determinants - Exercise 6.1 [Page 10]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 5 Determinants
Exercise 6.1 | Q 10.2 | Page 10

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