If you turn left at this intersection, do you have the right of way over the vehicle approaching from the opposite direction?

Why?

The A-5 sign warns of a junction of roads of equal priority. When turning left, you must give way to an oncoming vehicle travelling straight ahead or turning right. The car shown is approaching from the opposite direction, so you must let it pass before making your turn.

art. 25 ust. 1 Prawa o ruchu drogowym; znak A-5 „skrzyżowanie dróg”