Question

A boat crosses a river of width 123 m in which
the current has a uniform speed of 1.49 m/s.
The pilot maintains a bearing (i.e., the direction in which the boat points) perpendicular
to the river and a throttle setting to give a
constant speed of 2.66 m/s relative to the water.
What is the magnitude of the speed of the
boat relative to a stationary shore observer?
Answer in units of m/s.

Answer 1

heading (i.e., the direction in which the boat points)
You steer on a heading.
You take a bearing on something else.
Any way:
speed component across = 1.49 m/s
speed component downstream = 2.66
the components are perpendicular to each other so
magnitude of speed = sqrt(1.49^2+2.66^2)
= sqrt( 2.22+7.08)
= 3.05 m/s

Answer 2

People who write math texts apparently do not go to sea.