Question:
If the system of equations is inconsistent, then k =
$3 x+y=1$
$(2 k-1) x+(k-1) y=2 k+1$
(a) 1
(b) 0
(c) $-1$
(d) 2
Solution:
The given system of equations is inconsistent,
$3 x+y=1$
$(2 k-1) x+(k-1) y=2 k+1$
If the system of equations is in consistent, we have
$a_{1} b_{2}-a_{2} b_{1}=0$
$3 \times(k-1)-1(2 k-1)=0$
$3 k-3-2 k+1=0$
$1 k-2=0$
$1 k=2$
Therefore, the value of $k$ is 2 .
Hence, the correct choice is $d$.