In this situation, are you allowed to drive into the intersection without stopping in front of the line consisting of triangles?

At the junction, traffic is being directed by a police officer who is standing with his side towards you. This position means permission to enter the junction. The line made of triangles on the roadway is a give-way line (linia warunkowego zatrzymania) - you stop before it only when you have to give way to someone. Since the police officer is letting you through, you enter without stopping.

The Regulation on road signs and signals says that the position in which the person directing traffic stands with their side towards approaching vehicles means permission to enter the junction, and that marking P-13 shows the place where you stop in order to give way as required by sign A-7. Instructions from the person directing traffic take priority over signs, so when the police officer lets you go, sign A-7 no longer requires you to give way.

Legal basis: § 108 para. 2 and § 89 para. 2 of the Regulation on road signs and signals; Art. 5 para. 2 of the Road Traffic Act (Prawo o ruchu drogowym)