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2x − Y = 17 3x + 5y = 6 - Mathematics

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प्रश्न

2x − y = 17
3x + 5y = 6

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उत्तर

\[\text{ Given }: 2x - y = 17\] 
\[ 3x + 5y = 6\] 
Using Cramers Rule, we get 
\[D = \begin{vmatrix} 2 & - 1 \\3 & 5 \end{vmatrix} = 10 + 3 = 13\] 
\[ D_1 = \begin{vmatrix} 17 & - 1 \\ 6 & 5 \end{vmatrix} = 85 + 6 = 91\] 
\[ D_2 = \begin{vmatrix} 2 & 17 \\ 3 & 6 \end{vmatrix} = 12 - 51 = - 39\] 
Now,
\[x = \frac{D_1}{D} = \frac{91}{13} = 7\] 
\[y = \frac{D_2}{D} = \frac{- 39}{13} = - 3\] 

\[ \therefore x = 7\text{ and }y = - 3\] 

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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 3 | पृष्ठ ८४

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