posted by Megan .
A boater wants to head straight across a river that has a current of 3km/hr. If the top speed of the boat in still water is 4km/hr, find the direction the boat must travel into the current to go straight across the river. How fast is the boat going straight across the river?
Assume current is moving due south(270o).
Vb = 4 - 3i.
tanA = -3/4 = -0.75
A = -36.9o = 36.9o South of East.
Vb = 4/cos36.9 = 5 km/h = Velocity of
The boat must travel 5 km/h @ 36.9o North of East.