MathDB
angle chasing in a figure (2021 Novosibirsk Oral Geo Oly 8.3)

Source:

May 24, 2021
geometryangles

Problem Statement

Find the angle BCABCA in the quadrilateral of the figure. https://cdn.artofproblemsolving.com/attachments/0/2/974e23be54125cde8610a78254b59685833b5b.png