Find the value of k for which the system of equations 3x + y = 1 and kx + 2y = 5 has (i) a unique solution, (ii) no solution.

The given system of equations is 3x + y = 1 and kx + 2y = 5.


We know that the general form for a pair of linear equations in 2 variables x and y is a1x + b1y + c1 = 0


and a2x + b2y + c2 = 0.


Comparing with above equations,


we have a1 = 3, b1 = 1, c1 = - 1; a2 = k, b2 = 2, c2 = - 5





i) For the given system of equations to have a unique solution,




k 6


For k ≠ 6, the given system of equations has a unique solution.


ii) For the given system of equations to have no solution,




k = 6


For k = 6, the given system of equations has no solution.


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