Right Triangle, Incircles, Inradius. Level: High School, SAT
Prep, College geometry
The figure shows a right
ABC, r is the
Point D is taken on side AC, the
of triangles ABC, ABD and BDC touches the sides at E, F,
G, H, J, K, L, M, and N, respectively. Prove that DN = GK = EH
and r = BJ - DL Solution / comment.