How do you calculate resultant velocity?

[chestycougth]

Say I have a boat moving at 10 m/s south (160 degrees) ina river that is flowing at 3 m/s east (90 degrees)

How would you calculate the resultant velocity in this instance?

 

[DennisN]

Do you know about trigonometry and vectors? (hint: draw the velocities as vectors)

(by the way, are you sure you don't mean 180 degrees when you said "south"?)