MathDB
Find the length of CN in triangle ABC - Iran First Round 2018, P10

Source:

March 7, 2021
geometry

Problem Statement

Consider a triangle ABCABC in which AB=AC=15AB=AC=15 and BC=18BC=18. Points DD and EE are chosen on CACA and CBCB, respectively, such that CD=5CD=5 and CE=3CE=3. The point FF is chosen on the half-line DE→\overrightarrow{DE} so that EF=8EF=8. If MM is the midpoint of ABAB and NN is the intersection of FMFM and BCBC, what is the length of CNCN?