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What does the value of $z$ have to be in order to make the following equation true?

$$3\begin{bmatrix}2&-5\\\ 4&-7\end{bmatrix}=\begin{bmatrix}8&4\\\ 12&-9\end{bmatrix}+\begin{bmatrix}-2&-19\\\ 0&2z\end{bmatrix}$$

$6$

$1$

$3$

$-1$

$-6$