theorem :: JORDAN6:27

for P being Subset of (TOP-REAL 2)
for p1, p2, q1, q2 being Point of (TOP-REAL 2) st P is_an_arc_of p1,p2 & LE q2,q1,P,p2,p1 holds
LE q1,q2,P,p1,p2 by Th18, JORDAN5B:14;