D to A and B, and call E the intersection of D
B with the line through P and
Q (Figure 1). Thus we have constructed triangle MBD with cevians D
A
, ME,
and BC. We show that the segment D
A cuts the chord P Q at the same point Y
as BC, i.e., that the three cevians are concurrent at Y . This property will be proved
by applying Ceva’s theorem to triangle MBD
.
Lem