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**thereddevils** Say i have a matrix ,

$\displaystyle \begin{bmatrix}{4}&{3}\\{-1}&{7}\end{bmatrix}+5$ Mr F says: This makes no sense. Is this what the question said? Are you sure it didn't say $\displaystyle {\color{red}\begin{bmatrix}{4}&{3}\\{-1}&{7}\end{bmatrix}+5{\color{blue}I} }$ ....?

is it correct if i do it this way ,

$\displaystyle \begin{bmatrix}{4}&{3}\\{-1}&{7}\end{bmatrix}+5\begin{bmatrix}{1}&{0}\\{0}& { 1}\end{bmatrix}$

$\displaystyle =\begin{bmatrix}{9}&{3}\\{-1}&{12}\end{bmatrix}$

is 5 a scalar = 5I where I is an identity matrix ?