Where
\begin{bmatrix}
a & b & c \\
d & e & f \\
g & h & i\\
\end{bmatrix} WHERE THIS MATRIX EQUALS 7
\begin{bmatrix}
a & b & c \\
d & e & f \\
3g & 3h & 3i\\
\end{bmatrix}
FIND THE DETERMINATES OF THIS MATRIX
$|A B | = |A||B|$
$\begin{pmatrix}a &b &c \\d &e &f \\3g &3h &3i \end{pmatrix} = \begin{pmatrix}1 &0 &0 \\0 &1 &0 \\0 &0 &3 \end{pmatrix} \begin{pmatrix}a &b &c \\d &e &f \\g &h &i \end{pmatrix} $
$\left |\begin{pmatrix}a &b &c \\d &e &f \\3g &3h &3i \end{pmatrix}\right | = \left | \begin{pmatrix}1 &0 &0 \\0 &1 &0 \\0 &0 &3 \end{pmatrix}\right | \left | \begin{pmatrix}a &b &c \\d &e &f \\g &h &i \end{pmatrix}\right | = 3 \cdot 7 = 21$