Select the correct answer from the drop-down menu.
Fill in the missing number in the equation.

Answer:
8
Step-by-step explanation:
a A + b A where A is a matrix and a and b are scalars
( a+b) A
3+5 [tex]\left[\begin{array}{cc}-1&2\\4&-5\end{array}\right][/tex] = 8[tex]\left[\begin{array}{cc}-1&2\\4&-5\end{array}\right][/tex]