Question

Matrices help (screen shot attached)

Answer 1

matrices A and B are the same dimensions, 3-by-3
so they can be added together

the sum will also be a 3-by-3 matrix (say C)

the first element of C will be c_11 (top left) will be equal to

a_11 + b_11 the sum of the first elements of A and B

Answer 2

so in this case
the first element
\[c_{11} = a_{11} + b_{11}\]\[\qquad = 3 \ + \ 9\]\[\qquad = 14\]

Answer 3

Im confused...are you telling me the answer is C?

Answer 4

oh...so A?

Answer 5

i'm not telling you the answer, i'm trying to explain how to add matrices

Answer 6

but it doesnt make sense...3+9 isnt 14

Answer 7

all the elements of C (say \(c_{ij}\) )
are simply the sum of the corresponding elements of A and B \[c_{ij} =a_{ij}+b_{ij}\]

Answer 8

nevermind. ive figured it out

Answer 9

\[A+B\\=\begin{bmatrix}3&8&-2\\-1&5&2\\9&-3&4\end{bmatrix}+
\begin{bmatrix}9&2&6\\2&5&5\\3&5&2\end{bmatrix}\\=
\begin{bmatrix}14&(8+2)&(-2+6)\\(-1+2)&(5+5)&(2+5)\\(9+3)&(-3+5)&(4+2)\end{bmatrix}\\=\quad\dots\]