Answer:
[tex]\large\boxed{\left[\begin{array}{ccc}10&-30\\-10&-2\end{array}\right]}[/tex]
Step-by-step explanation:
[tex]X-3\left[\begin{array}{ccc}2&-8\\-4&2\end{array}\right] =\left[\begin{array}{ccc}4&-6\\2&-8\end{array}\right]\\\\X-\left[\begin{array}{ccc}(3)(2)&(3)(-8)\\(3)(-4)&(3)(2)\end{array}\right]=\left[\begin{array}{ccc}4&-6\\2&-8\end{array}\right]\\\\X-\left[\begin{array}{ccc}6&-24\\-12&6\end{array}\right]=\left[\begin{array}{ccc}4&-6\\2&-8\end{array}\right][/tex]
[tex]X-\left[\begin{array}{ccc}6&-24\\-12&6\end{array}\right]+\left[\begin{array}{ccc}6&-24\\-12&6\end{array}\right]=\left[\begin{array}{ccc}4&-6\\2&-8\end{array}\right]+\left[\begin{array}{ccc}6&-24\\-12&6\end{array}\right]\\\\X=\left[\begin{array}{ccc}4+6&(-6)+(-24)\\2+(-12)&-8+6\end{array}\right]\\\\X=\left[\begin{array}{ccc}10&-30\\-10&-2\end{array}\right][/tex]
