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Question
3x + y = 5
− 6x − 2y = 9
Solution
Given: 3x + y = 5
− 6x − 2y = 9
\[D = \begin{vmatrix}3 & 1 \\ - 6 & - 2\end{vmatrix} = - 6 + 6 = 0\]
\[ D_{1 =} \begin{vmatrix}5 & 1 \\ 9 & - 2\end{vmatrix} = - 10 - 9 = - 19\]
\[ D_2 = \begin{vmatrix}3 & 5 \\ - 6 & 9\end{vmatrix} = 27 + 30 = 57\]Here, D1 and D2 are non-zero, but D is zero. Thus, the system of linear equations is inconsistent.
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