∀ {V : Type u_1} {P : Type u_2} [inst : NormedAddCommGroup V] [inst_1 : InnerProductSpace ℝ V] [inst_2 : MetricSpace P]
  [inst_3 : NormedAddTorsor V P] [hd2 : Fact (Module.finrank ℝ V = 2)] [inst_4 : Module.Oriented ℝ V (Fin 2)]
  {p₁ p₂ p₃ : P},
  EuclideanGeometry.oangle p₁ p₂ p₃ = ↑(Real.pi / 2) → dist p₁ p₂ / (EuclideanGeometry.oangle p₂ p₃ p₁).tan = dist p₃ p₂