Answer
$10$
Work Step by Step
For any matrix \[
\left[ {\begin{array}{cc}
a & b \\
c & d \\
\end{array} } \right]
\] the determinant equals $ad-bc$. For the matrix \[
\left[ {\begin{array}{cc}
0 & -2 \\
5 & 1 \\
\end{array} } \right]
\] the determinant equals $0(1)-(-2)(5)=10.$