The correlation that transforms the four vertices [math]Q, R, S, T[/math] of the pentagon [math]PQRST[/math] into the four sides [math]q = ST, r = TP, s = PQ, t = QR[/math] also transforms the three sides [math]t = QR, p = RS, q=ST[/math] into the three vertices [math]T = q\cdot r, P = r\cdot s, Q = s \cdot t[/math], and the "diagonal point" [math]A = q\cdot t[/math] into the "diagonal line" [math]a = QT[/math].Thus it transforms each vertex of the triangle [math]AQT[/math] into the opposite side.