Fred rows his small boat directly across a river, which is 4 mi wide. There is a 5 mi/h current. When he reaches the opposite shore, Fred finds that he has landed at a point 2 mi downstream.
a. Write the equation that describes the effect of the river current.
b. If Fred's boat can go s mi/h, what equation describes his contribution to the motion?
c. Solve the system of equations from 7a and 7b for s so that he reaches the correct point 2 mi downstream on the opposite shore.
d. How far did Fred actually travel?
e. How long did it take him?
f. What was Fred's actual speed?
g. As the boat travels down the river, what angle does it make with the riverbank?