Answer
$-236.$
Work Step by Step
We know that for a matrix
\[
\left[\begin{array}{rrr}
a & b & c \\
d &e & f \\
g &h & i \\
\end{array} \right]
\]
the determinant, $D=a(ei-fh)-b(di-fg)+c(dh-eg).$
Hence here $D=4(6\cdot(-4)-0\cdot2)-7((-5)\cdot(-4)-0\cdot3)+0(-5\cdot2-6\cdot3)=4\cdot(-24)-7\cdot20+0\cdot-28=-96-140+0=-236.$
