Question

If the value of $\left|\begin{array}{ccc}1& 2& 4\\ -1& 3& 0\\ 4& 1& 0\end{array}\right|$ is $k$, then find $\frac{-k}{13}$.

Answer 1

$k=\left|\begin{array}{ccc}1& 2& 4\\ -1& 3& 0\\ 4& 1& 0\end{array}\right|$

$k=1\left(0\right)-2\left(0\right)+4(-1-12)$

$k=-4\left(13\right)$

Now,$\frac{-k}{13}=\frac{-(-4)\left(13\right)}{13}$

$=4$

$\therefore$ There the correct answer is $4$