Answer
\[0\]
Work Step by Step
\[\begin{gathered}
\left| {\begin{array}{*{20}{c}}
4&0 \\
{ - 2}&0
\end{array}} \right| \hfill \\
{\text{Evaluate the determinant, recall that}} \hfill \\
\left| {\begin{array}{*{20}{c}}
a&b \\
c&d
\end{array}} \right| = ad - bc \hfill \\
{\text{Then,}} \hfill \\
\left| {\begin{array}{*{20}{c}}
4&0 \\
{ - 2}&0
\end{array}} \right| = \left( 4 \right)\left( 0 \right) - \left( 0 \right)\left( { - 2} \right) \hfill \\
\left| {\begin{array}{*{20}{c}}
4&0 \\
{ - 2}&0
\end{array}} \right| = 0 \hfill \\
\end{gathered} \]