If $A$ is the $22$ matrix given by

$A=\left[\begin{array}{cc}a& b\\ c& d\end{array}\right]$

and if $ad-bc0,$ the inverse is given by

$A^{-1}=\frac{1}{ad-bc}\left[\begin{array}{cc}d& -b\\ -c& a\end{array}\right].$

Use the formula above to find the inverse of the $22$ matrix $($if it exists$).($If an answer does not exist, enter DNE in any single blank.$)$

$\left[\begin{array}{cc}3& 4\\ -1& 5\end{array}\right]$

Need Help?