Evaluate Each Determinant $\operatorname{det}\left[\begin{array}{rr}8 & 6 \\ -2 & -7\end{array}\right]$ (B) $\operatorname{det}\left[\begin{array}{rrr}1 & 3 & 4 \\ -2 & 4 & 5 \\ 7 & 6 & -3\end{array}\right]$

Short Answer

Evaluate each determinant.
(a) $\operatorname{det}\left[\begin{array}{rr}8 & 6 \\ -2 & -7\end{array}\right]$
(b) $\operatorname{det}\left[\begin{array}{rrr}1 & 3 & 4 \\ -2 & 4 & 5 \\ 7 & 6 & -3\end{array}\right]$