A straight river is 20 m wide. The velocity of the river at (x, y) is

A boat leaves the shore at (0, 0) and travels through the water with a constant velocity. It arrives at the opposite shore at (20, 0). The speed of the boat is always radical 20 m/min.

a. Find the velocity of the boat.

b. Find the location of the boat at time t.

c. Sketch the path of the boat.

I figured the velocity of the boat, since traveling in the positive direction on the x axis, would also be radical 20 m/min. The boat seems to cross the river and end up DIRECTLY across, so I tried to set up a right triangle where the hypotenuse represented the boats velocity (radical 20) and the vertical leg represented the river velocity (-40 m/min? calculated using the integral of the equation from 1 to 20?). I'm not sure what I'm doing and an totally stuck. Thank you.