MathDB
similar triangle by segments of triangle sides

Source: II Soros Olympiad 1995-96 R3 11.10 https://artofproblemsolving.com/community/c2416727_soros_olympiad_in_mathematics

June 6, 2024
geometrytriangle inequality

Problem Statement

All sides of triangle ABCABC are different. On rays BAB A and CAC A the segments BKB K and CMCM are laid out, equal to side BCBC. Let us denote by xx the length of the segment KMKM. In the same way, by plotting the side ACAC on the rays ABAB and CBCB from AA and CC, we obtain a segment of length yy, and by plotting the side AB on the rays ACAC and BCBC, we obtain a segment of length zz. a) Prove that a triangle can be formed from the segments xx, yy and zz, and this triangle is similar to triangle ABCABC. b) Find the radius of the circumcircle of a triangle with sides xx, yy and zz, if the radii of the circumscribed and inscribed circles of triangle ABCABC are equal to RR and rr respectively.