Question

If the system of linear equations
$(\cos \theta )x+(\sin \theta )y+\cos \theta =0$
$(\sin \theta )x+(\cos \theta )y+\sin \theta =0$
$(\cos \theta )x+(\sin \theta )y-\cos \theta =0$
is consistent, then the number of possible values of $\theta ,\theta \in [0,2\pi ]$ is

Answer 1

Answer: 2

Correct answer is (b)