Answer:
14
Step-by-step explanation:
b22 = 2×a22 = 2×7 = 14
__
Multiplication of a matrix by a scalar is the same as multiplying every element of that matrix by that scalar.
[tex]B=2A=2\left[\begin{array}{cc}8&-2\\4&7\end{array}\right]=\left[\begin{array}{cc}16&-4\\8&14\end{array}\right]\\\\b_{22}=14[/tex]
