Different Order, but Same Answer

To draw the diagram follow the rules with b as the starting vector:

1. Draw the first vector b as an arrow with its tail at the origin.
2. Draw the second vector a as an arrow with its tail at the point of the first.
3. The sum is the arrow from the origin to the tip of the second vector.

(Remember that vectors have no location so you can draw a picture of a vector with its tail starting on any point you want.)

Since vector addition is commutative, the result must be the same.