MathDB
Find $r_1+r_2$

Source: Moldova TST 1998

August 8, 2023
geometry

Problem Statement

Two triangles ABCABC and BDEBDE have vertexes CC and EE on the same side of the line ABAB{} and AB=a<BDAB=a<BD. Denote {P}=CEAB\{P\}=CE\cap AB and γ=m(CPA)\gamma=m(\angle CPA). Let r1r_1 be the radius of the inscribed cricle of triangle PACPAC and r2r_2 the radius of the excircle of triangle PDEPDE, tangent to the side DEDE. Find r1+r2r_1+r_2.