MathDB
Everything is integer

Source: Hungary

July 1, 2020
geometry

Problem Statement

Let TT be any triangle such that its side-lengths a,ba, b and cc and its circumradius RR are positive integers. Show that: a) the inradius rr of TT is a positive integer; b) the perimeter PP of TT is a multiple of 44; and c) all three of a,ba, b and cc are even.