A plane flies due north (90° from east) with a velocity of 100 km/h for 3 hours. During this time, a steady wind blows southeast at 30 km/h at an angle of 315° from due east. After 3 hours, where will the plane’s position be relative to its starting point?

Question

PLEASE explain what this 315° angle means? This is a problem related to triangles and a triangle can only have 180° for total angles. I assumed this meant that I would do 315-270 to get the difference between the axis and the angle, which results in 45°. However, everything online says otherwise but they gloss over the fact that a triangle can't be more than 180°.

Answer 1

they use the unit circle ... 360º ... E (0º), N (90º), W (180º), S (270º)

so the wind is pushing the plane south and east

after 3 hr
... north ... 3[100 - (30 / √2)]
... east ... 3 (30 / √2)

Answer 2

I believe the question is asking for the displacement distance in kilometers, and the angle of change from the starting point?

Answer 3

use the Pythagorean theorem, and note that
tan(90-θ) = y/x