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Given: X + 2y = 1 3x + Y = 4 - Mathematics

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प्रश्न

Given: x + 2y = 1
            3x + y = 4

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उत्तर

\[D = \begin{vmatrix}1 & 2 \\ 3 & 1\end{vmatrix} = - 5\] 

\[ D_1 = \begin{vmatrix}1 & 2 \\ 4 & 1\end{vmatrix} = - 7\] 

\[ D_2 = \begin{vmatrix}1 & 1 \\ 3 & 4\end{vmatrix} = 1\] 

\[Now, \] 

\[x = \frac{D_1}{D} = \frac{7}{5}\] 

\[y = \frac{D_2}{D} = - \frac{1}{5}\]  

\[ \therefore x = \frac{7}{5}\text{ and }y = - \frac{1}{5}\] 

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अध्याय 6: Determinants - Exercise 6.4 [पृष्ठ ८४]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 6 Determinants
Exercise 6.4 | Q 10 | पृष्ठ ८४

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