Question

PLEASE HELP I'm having trouble ​

Answer 1

Answer:

$c_{11}=56.1$

$c_{12}=12.1$

$c_{13}=236$

Step-by-step explanation:

• The product of two matrices $X_{m\times{n}}$ and  $Y_{n\times{r}}$ equals a matrix $M_{m\times{r}}$, where the first element of the subscript represents the amount of files of the matrix and the second element represents the amount of columns of the matrix.
• Then, in this case  $A_{1\times{3}}$   $B_{3\times{3}}$, therefore, its product will result a matrix $C_{1\times{3}}$.
• Because C matrix is going to have an only file and three columns, we now have to find the values of the elements in each column, based on the elements of A and B.
• Commonly, to obtain the values of the resulting matrix, we just have to multiply each file of the first matrix by each column of the second matrix and sum, as follows:

1. $c_{11}=77\times1.2+39\times2.2-33\times3.7=56.1$
2. $c_{12}=77\times1.4+39\times1.1-33\times4.2=12.1$
3. $c_{13}=77\times3.1+39\times5.6-33\times6.7=236$

• Finally, C matrix is $\begin{pmatrix}\56.1 & 12.1& 236\end{pmatrix}$