Find the determinant of the matrix:
\[A = \begin{bmatrix} 1 & 2 \\ -12 & -9 \end{bmatrix}\]Click for (rounded) answer
Click for Latex code
\[
\begin{bmatrix}
1 & 2 \\
-12 & -9
\end{bmatrix}
\]
Determinant:
\begin{solution}
\[
\det A = 15
\]
\end{solution}