Adding two vectors on a grid

What does the sum mean on a grid? Vector A is 5 to the right and 2 up. Vector B is 2 to the right and 4 up. To add them, start B where A ends: $\displaystyle A+B$ goes from the start of $\displaystyle A$ to the end of $\displaystyle B$, 7 to the right and 6 up. That is the vector $\displaystyle \begin{pmatrix}7\\6\end{pmatrix}$, the answer the calculator gave.