Question

Evaluate -1/2A when

Answer 1

Answer: B, No solution

Actual answer is:

[-1.33 -5]
[-2 -4]

Answer 2

Multiplying a matrix by a scalar is very simple: you only have to multiply every entry of the matrix by that scalar.

So, we have

$A=\left[\begin{array}{cc}-\dfrac{4}{3}&-5\\-2&-4\end{array}\right]\implies -\dfrac{1}{2}A=\left[\begin{array}{cc}-\dfrac{1}{2}\left(-\dfrac{4}{3}\right)&-\dfrac{1}{2}(-5)\\-\dfrac{1}{2}(-2)&-\dfrac{1}{2}(-4)\end{array}\right]=\left[\begin{array}{cc}\dfrac{2}{3}&\dfrac{5}{2}\\1&2\end{array}\right]$