Question

Find the value of $k$ for which the following system of equations has no solution:
$2x+ky=11$
$5x-7y=5$

Answer 1

For the system to have no solution, lines must be parallel

$\Rightarrow$ratio of respective 'x' and 'y' coefficients must be equal

$\Rightarrow \frac{2}{5}=\frac{k}{-7}$

$\Rightarrow k=\frac{-14}{5}$