Given a matrix [tex]A[/tex] an element inside a matrix is denoted by [tex]A_{ij}[/tex] where [tex]i[/tex] is a number of a row and [tex]j[/tex] is a number of a column in which the element is in.
Your matrix is called [tex]W[/tex] and it equals to,
[tex]W=\begin{bmatrix}28&21&19\\17&24&15\\22&29&17\\\end{bmatrix}[/tex]
So [tex]W_{11}[/tex] will denote the element in the first row and first column that is [tex]\boxed{W_{11}=28}[/tex].
Hope this helps :)
