Join the USAMO Guide Discord Server. Regular updates are posted there!
From module Geometry Basics
If ∠A=20∘\angle A=20^{\circ}∠A=20∘ and ∠AFG=∠AGF\angle AFG=\angle AGF∠AFG=∠AGF, then ∠B+∠D=\angle B+\angle D=∠B+∠D= [See figure in original PDF]
Select an answer
← Back to all problems