Quote:
Originally Posted by mfgoode
In triangle AHC , R and N are midpoints.
Therefore RH is // to HC

A typo, perhaps? RH and HC should make an X, unless I miss something.
P.S: A clearer drawing could've helped me see some things. The triangle AMN is similar to triangle ABC, in the sense that is only scaled down. AM/2 = AB, MN/2 = BC and AN = AC/2, therefore their angles are equal.