Explore various positions for the vertices of the triangle and the points L, M, and N to verify the following result: If three proper Cevian lines are concurrent, then d = 1. Find examples of concurrent Cevian lines in which all three of the points L, 8.2. Sensed ratios and ideal points 65 M, and N lie on the triangle AABC and other examples in which at least one of the three points is not on AABC. Verify that d - 1 in all cases in which the proper Cevians are concurrent.