Answer
-78
Work Step by Step
We evaluate the determinant of the matrix using Cramer's rule, which is listed on page 203. Doing this, we find:
$$\det \begin{pmatrix}-5&12\\ 4&6\end{pmatrix} \\ \left(-5\right)\cdot \:6-12\cdot \:4\\ -78$$
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.