Number 1
Given
[tex]\begin{bmatrix}{5} & {1} \\ {-4} & {0}\end{bmatrix}[/tex]
Solution
The determinant formula
[tex]\begin{bmatrix}{a} & {b} \\ {c} & {d}\end{bmatrix}=ad-bc[/tex]
Now apply the determinant formula
[tex]\begin{gathered} \begin{bmatrix}{5} & {1} \\ {-4} & {0}\end{bmatrix}=(5\times0)-(1\times-4) \\ \\ \begin{bmatrix}{5} & {1} \\ {-4} & {0}\end{bmatrix}=0-(-4) \\ \\ \begin{bmatrix}{5} & {1} \\ {-4} & {0}\end{bmatrix}=0+4 \\ \\ \begin{bmatrix}{5} & {1} \\ {-4} & {0}\end{bmatrix}=4 \end{gathered}[/tex]
The final answer
[tex]\begin{bmatrix}{5} & {1} \\ {-4} & {0}\end{bmatrix}=4[/tex]
