Given:
$A = \left[ \begin{array} { r r r } 8 & - 7 & 0 \ - 5 & - 2 & 3 \end{array} \right] , B = \left[ \begin{array} { r r r } 3 & 0 & 7 \ 4 & 9 & - 2 \end{array} \right] , c = 8$ and $d = - 3$ determine $c A + d B$.
A) $\left[ \begin{array} { r r r } 55 & - 7 & 7 \ - 52 & 7 & 1 \end{array} \right]$
B) $\left[ \begin{array} { r r r } 73 & - 56 & 21 \ - 28 & 11 & 18 \end{array} \right]$
C) $\left[ \begin{array} { r r r } 55 & - 56 & - 21 \ - 52 & - 43 & 30 \end{array} \right]$
D) $\left[ \begin{array} { r r r } 55 & - 56 & - 21 \ - 1 & 7 & 1 \end{array} \right]$
E) not possible

Question

Quizplus · Accepted Answer

To find $cA + dB$, multiply each element of matrix $A$ by $c$ and each element of matrix $B$ by $d$, then add the corresponding elements. For $cA$, multiply each element of $A$ by $8$, and for $dB$, multiply each element of $B$ by $-3$. The calculation yields $cA + dB = \left[ \begin{array} { r r r } 64 - 9 & -56 + 0 & 0 - 21 \ -40 - 12 & -16 - 27 & 24 + 6 \end{array} \right] = \left[ \begin{array} { r r r } 55 & -56 & -21 \ -52 & -43 & 30 \end{array} \right]$.

Given And d=−3d = - 3d=−3 Determine cA+dBc A + d BcA+dB

Given And $d = - 3$ Determine $c A + d B$