Question

Fine -4A+6B (Picture provided)

Answer 1

Answer:

Option a

$-4A+6B=\left(\begin{array}{ccc}-22&30&32\\-16&-78&48\\42&24&30\end{array}\right)$

Step-by-step explanation:

First multiply matrix A by -4.

Then multiply the matrix B by 6.

When multiplying a matrix by a number x you must multiply each element of the matrix by x.

Then we perform operation -4A

$-4\left(\begin{array}{ccc}-2&6&1\\1&9&-6\\-9&9&-9\end{array}\right)=\left(\begin{array}{ccc}8&-24&-4\\-4&-36&24\\36&-36&36\end{array}\right)$

Now we perform operation 6B

$6\left(\begin{array}{ccc}-5&9&6\\-2&-7&4\\1&10&-1\end{array}\right)=\left(\begin{array}{ccc}-30&54&36\\-12&-42&24\\6&60&-6\end{array}\right)$

Now we add the resulting matrices

$\left(\begin{array}{ccc}8&-24&-4\\-4&-36&24\\36&-36&36\end{array}\right)+\left(\begin{array}{ccc}-30&54&36\\-12&-42&24\\6&60&-6\end{array}\right)=\left(\begin{array}{ccc}-22&30&32\\-16&-78&48\\42&24&30\end{array}\right)$