Perform the indicated matrix operations.
-Let $A = \left[ \begin{array} { l l } - 4 & 2 \end{array} \right]$ and $B = \left[ \begin{array} { l l } 1 & 0 \end{array} \right]$. Find $3 A + 4 B$.
A) $\left[ \begin{array} { l l } - 1 & 2 \end{array} \right]$
B) $[ - 74 ]$
C) $\left[ \begin{array} { l l } - 8 & 6 \end{array} \right]$
D) $[ - 124 ]$

Question

Quizplus · Accepted Answer

First, multiply each matrix by its scalar: $3A = 3 \times \left[ \begin{array} { l l } - 4 & 2 \end{array} \right] = \left[ \begin{array} { l l } - 12 & 6 \end{array} \right]$ and $4B = 4 \times \left[ \begin{array} { l l } 1 & 0 \end{array} \right] = \left[ \begin{array} { l l } 4 & 0 \end{array} \right]$. Then, add the resulting matrices: $\left[ \begin{array} { l l } - 12 & 6 \end{array} \right] + \left[ \begin{array} { l l } 4 & 0 \end{array} \right] = \left[ \begin{array} { l l } - 8 & 6 \end{array} \right]$.

Perform the Indicated Matrix Operations A=[−42]A = \left[ \begin{array} { l l } - 4 & 2 \end{array} \right]A=[−4​2​]

Perform the Indicated Matrix Operations $A = \left[ \begin{array} { l l } - 4 & 2 \end{array} \right]$