Online Geometry Problem 707: Triangle, Excenters, Angle Bisectors,
Angle, Measurement.
Level: High School, Honors Geometry, College,
Mathematics Education
The figure shows a triangle ABC, AD meets
BC at F and AE meets BC at G. D is the excenter of triangle ABG
corresponding to BG and E is the excenter of triangle AFC corresponding
to FC. If angle ADE + angle AED = 142 degrees, find angle ADB + angle
AEC.