Add and subtract matrices
Matrix \(Q\) records the points scored by each team in round 1 of a school athletics carnival, and matrix \(D\) records the points scored by the same teams in round 2
In both matrices, the rows are Barton, Chisholm (top to bottom) and the columns are Relay, Sprint (left to right)
\[Q = \begin{bmatrix} 7 & 3 \\ 11 & 9 \end{bmatrix}\]
\[D = \begin{bmatrix} 7 & 3 \\ 9 & 1 \end{bmatrix}\]