A resultant vector is the resultant of adding vectors together, these vectors may represent forces. For example, you push a box with a force 2N one way, and someone else pushes it with 5N another way, which way does it move? There are two ways of calculating a resultant 2-dimensional vector.

- Draw all the vectors accurately on a piece of paper, with the start of each vector starting at the end of the previous vector. You will end up with lots of lines added together, if you draw a line from the start of the new line to the end of it you will end up with a resultant vector.
- The second way is to resolve each vector in two planes at 90 degrees (pi/2 radians) to each other. You then add up all the components on your axis. You will end up with a point on your graph on which if you draw a line from the origin to that point you will have a resultant vector. Trigonometry helps!