A ship started sailing 42.58 degrees west of south at the rate of 15 kph. after 2 hours, ship B started at the same port going 46.33 degrees west of north at the rate of 7 kph. after how many hours will the second ship be exactly north of ship A?

Answer 1

you are just interested in the east-west distances traveled. When they are the same, B is north of A. So, t hours after A set off, you want

(15 sin42.58°)t = (7 sin46.33°)(t-2)

This has a solution of t = -2

huh? I suspect a typo. A is going twice as fast, for two hours longer, and at almost the same E-W speed. No way could B catch up to it.