A swimmer heads directly across a river, swimming at 1.4 m/s relative to the water. She arrives at a point 48 m downstream from the point directly across the river, which is 74 m wide. What is the speed of the river current? What is the swimmer's speed relative to the shore? In what direction should the swimmer head so as to arrive at the point directly opposite her starting point?
I'm guessing it's a mixture of x=v*t and the Pythagorean theorem.
The Attempt at a Solution
So, Displacement=83.2 m, which I figured out by making a triangle with the vertical and horizontal displacement. There are so many moving parts I've gotten so confused! I know I have to use vectors somehow to make a triangle. 1.4 meters per second is the hypotenuse of the triangle based on velocity (I made two. One based on displacement and another on the velocity. I figured they couldn't be mixed, and I couldn't find a way to translate either one to make them the same.)