Triangle ABC is an isosceles right triangle with a right angle at A. Points D and E trisect side AC . What is the degree measure of angle \(BED\)?
Let AC = AB
tan (angle BEA) = AB / EA = AB / [1/3) AB) = 1/ (1/3) = 3
arctan 3 ≈ 71.6°
Angle BED ≈ 180 - 71.6 ≈ 108.4°
