For what value of k will the following system of linear equations has no solution:
3x + y = 1
(2k − 1)x + (k − 1)y = 2k + 1
The given system of equations is
3x + y = 1
(2k − 1)x + (k − 1)y = 2k + 1
Here, a1 = 3, b1 = 1, c1 = 1
a2 = 2k − 1, b2 = k − 1, c2 = 2k + 1
The given system of linear equations has no solution.
$\therefore \frac{a_{1}}{a_{2}}=\frac{b_{1}}{b_{2}} \neq \frac{c_{1}}{c_{2}}$
$\Rightarrow \frac{3}{2 k-1}=\frac{1}{k-1} \neq \frac{1}{2 k+1}$
$\Rightarrow \frac{3}{2 k-1}=\frac{1}{k-1}$ and $\frac{1}{k-1} \neq \frac{1}{2 k+1}$
Now,
$\frac{3}{2 k-1}=\frac{1}{k-1}$
$\Rightarrow 3 k-3=2 k-1$
$\Rightarrow 3 k-2 k=-1+3$
$\Rightarrow k=2$
When k = 2,
$\frac{1}{k-1}=\frac{1}{2-1}=1$ and $\frac{1}{2 k+1}=\frac{1}{2 \times 2+1}=\frac{1}{5}$
Thus, for $k=2, \frac{1}{k-1} \neq \frac{1}{2 k+1}$
Hence, the given system of linear equations will have no solution when k = 2.